The document provides guidelines for standardizing the alignment of different types of eyewear frames, including adjusting the bridge, temples, and nose pads to be properly aligned based on impersonal standards. It describes checking frames for horizontal and vertical alignment and adjusting plastic, metal, and rimless frames, noting that plastic frames require heating during adjustment while metal frames can often be adjusted without heating. The goal of standard alignment is to configure eyewear to fit comfortably and symmetrically on a variety of face shapes.
This document provides guidance on standard optical adjustments and repairs for eyeglasses. It discusses 10 key points to check during a standard alignment before dispensing glasses, including tightening screws, checking for lens misalignments, face form, pantoscopic tilt, and temple positioning. It also reviews common repairs like replacing loose or fallen screws and adjusting nose pads. The goal of adjustments is to have an even pressure across the four points of contact on the face for patient comfort.
It will provide the basic knowledge regarding special purpose frames.
Special purpose frames will provide the efficient benefits to the needed patients.
The document discusses various tools used for optical repairs, including different types of optical screwdrivers, flaring pliers, and screw-lift tools. It also describes the different types of nose pad assemblies, including screw-on and push-on pads. The document provides guidance on replacing broken parts like temples, plastic earpiece covers, and nose pads on frames. It notes that soldering, either with a flame or electric unit, is usually required to repair broken metal portions of frames.
1. Aspheric lenses have at least one surface that is not spherical, changing curvature over the surface rather than maintaining a single radius. This helps correct optical aberrations from off-axis viewing.
2. Early patented aspheric lenses included designs from 1976-1977 and 1980. Aspheric lenses aim to reduce optical aberrations from oblique vision through the lens.
3. Aspheric surfaces are based on conic sections including circles, ellipses, parabolas, and hyperbolas, classified by their p-value in an equation. Higher p-values indicate more oblate ellipses while lower negative values are more hyperbolic.
1. Standard plastic frames must be heated to adjust alignment, using either hot air, salt, or glass beads. The bridge and temples can be bent to correct horizontal, vertical, and coplanar alignment.
2. Temple spread, which is the angle of the temples from the front of the frame, should usually be 94-95 degrees. Temple spread can be adjusted by heating and bending the temples or endpieces.
3. Temples must be parallel to check for proper alignment. The flat surface test checks if both temples sit evenly. Causes of improper parallelism include bent endpieces, hinges, or temples.
This document discusses frame adjustment and quality checking. It describes 7 off-face adjustments including x-ing, temple spread, pantoscopic angle, temple fold angle, pad angles, face form, and 4-point touch. It also discusses 7 on-face adjustments including horizontal alignment, vertex distance, frame height, segment height, temple bend, pad contact, and skin/lash clearance. Key details are provided about properly adjusting specific angles and alignments during the fitting process.
The document discusses the base curve of lenses, which is the surface curve that forms the starting point for the remaining lens curve. It describes the importance of selecting the proper base curve, as it determines lens thickness, aberrations, and cosmetics. The document outlines different lens forms including Wollaston, Oswalt, and meniscus, discussing their optical properties. It notes that the best lens form follows mechanical and optical criteria, providing a thinner lens that is lighter in weight with reduced magnification and aberrations.
The document discusses pantoscopic tilt, which is when the bottom of eyeglass frames are angled toward the cheeks. It describes how proper pantoscopic tilt helps maximize the amount of bridge surface resting on the nose. The document also mentions retroscopic tilt, when the bottom of frames is angled away from the cheeks, and orthoscopic tilt, when frames have no angle. Additionally, it explains how lens tilt improves how glasses look and function for patients, and depends on ear and nose bridge heights, requiring frames to be properly adjusted for individual wearers before measurements.
This document provides guidance on standard optical adjustments and repairs for eyeglasses. It discusses 10 key points to check during a standard alignment before dispensing glasses, including tightening screws, checking for lens misalignments, face form, pantoscopic tilt, and temple positioning. It also reviews common repairs like replacing loose or fallen screws and adjusting nose pads. The goal of adjustments is to have an even pressure across the four points of contact on the face for patient comfort.
It will provide the basic knowledge regarding special purpose frames.
Special purpose frames will provide the efficient benefits to the needed patients.
The document discusses various tools used for optical repairs, including different types of optical screwdrivers, flaring pliers, and screw-lift tools. It also describes the different types of nose pad assemblies, including screw-on and push-on pads. The document provides guidance on replacing broken parts like temples, plastic earpiece covers, and nose pads on frames. It notes that soldering, either with a flame or electric unit, is usually required to repair broken metal portions of frames.
1. Aspheric lenses have at least one surface that is not spherical, changing curvature over the surface rather than maintaining a single radius. This helps correct optical aberrations from off-axis viewing.
2. Early patented aspheric lenses included designs from 1976-1977 and 1980. Aspheric lenses aim to reduce optical aberrations from oblique vision through the lens.
3. Aspheric surfaces are based on conic sections including circles, ellipses, parabolas, and hyperbolas, classified by their p-value in an equation. Higher p-values indicate more oblate ellipses while lower negative values are more hyperbolic.
1. Standard plastic frames must be heated to adjust alignment, using either hot air, salt, or glass beads. The bridge and temples can be bent to correct horizontal, vertical, and coplanar alignment.
2. Temple spread, which is the angle of the temples from the front of the frame, should usually be 94-95 degrees. Temple spread can be adjusted by heating and bending the temples or endpieces.
3. Temples must be parallel to check for proper alignment. The flat surface test checks if both temples sit evenly. Causes of improper parallelism include bent endpieces, hinges, or temples.
This document discusses frame adjustment and quality checking. It describes 7 off-face adjustments including x-ing, temple spread, pantoscopic angle, temple fold angle, pad angles, face form, and 4-point touch. It also discusses 7 on-face adjustments including horizontal alignment, vertex distance, frame height, segment height, temple bend, pad contact, and skin/lash clearance. Key details are provided about properly adjusting specific angles and alignments during the fitting process.
The document discusses the base curve of lenses, which is the surface curve that forms the starting point for the remaining lens curve. It describes the importance of selecting the proper base curve, as it determines lens thickness, aberrations, and cosmetics. The document outlines different lens forms including Wollaston, Oswalt, and meniscus, discussing their optical properties. It notes that the best lens form follows mechanical and optical criteria, providing a thinner lens that is lighter in weight with reduced magnification and aberrations.
The document discusses pantoscopic tilt, which is when the bottom of eyeglass frames are angled toward the cheeks. It describes how proper pantoscopic tilt helps maximize the amount of bridge surface resting on the nose. The document also mentions retroscopic tilt, when the bottom of frames is angled away from the cheeks, and orthoscopic tilt, when frames have no angle. Additionally, it explains how lens tilt improves how glasses look and function for patients, and depends on ear and nose bridge heights, requiring frames to be properly adjusted for individual wearers before measurements.
This document describes the process of hand neutralization to determine the power of an unknown lens. Hand neutralization involves using a lens of known power to neutralize an unknown lens, where neutralization occurs when movement of the image through the lens is eliminated, indicating the lenses have cancelling powers. The steps include drawing a cross, determining lens orientation and optical center, neutralizing each meridian by finding the lens power that eliminates movement, recording the results as a power cross, and converting to a spherocylindrical formula.
This document discusses the different parts and types of eyeglass frames. It defines the frame as the portion that holds the lenses in front of the eyes. The key parts are identified as the bridge, eyewire, endpieces, hinges, temples, and nose pads. Different frame materials like plastic, metal, and nylon are described. Various bridge, endpiece, and temple designs are outlined, including saddle, modified saddle, keyhole, and turn back styles. Frame types such as half-eyes, rimless, and combination frames are also summarized.
This document discusses prisms and their effects on light refraction. It begins by explaining how a prism deflects light toward its base, causing the perceived image to shift toward the apex. Various prism properties are then defined, such as prism diopters used to measure deviation. The document also covers using prisms in lenses to create decentralization by shifting the optical center. It provides an example calculation for applying a prism to a plus lens to achieve a desired 5mm nasal decentralization. By adding a prism with a 2.2 prism diopter nasal base, the optical center is shifted as needed.
Polarized lenses block certain types of light waves to reduce glare. They work by only allowing vertically polarized light to enter the eye, blocking out horizontally polarized light that causes glare when reflected off smooth surfaces like water or roads. Polarized lenses come in various colors and are useful for activities like driving, boating, and photography by improving contrast and reducing eye strain from glare. While effective at reducing most types of glare, polarized lenses have some limitations like not working as well with snow glare and possibly distorting displays.
This presentation is prepared in the process of me teaching Visual Optics for graduate level optometry students. It narrates the type, clinical manifestations, clinical assessment and treatment of Aniseikonia.
This document discusses aspheric lenses. It begins with a brief history of aspheric lens development from 1909 to 1980. It then covers terminology, the introduction of aspheric lenses which aim to reduce optical aberrations compared to spherical lenses. The document discusses various aspheric lens designs and how they can reduce peripheral aberrations and make lenses thinner. It also covers measuring aspheric lenses, uses of aspheric lenses, and benefits such as reduction of oblique astigmatism and thinner lens designs.
This document discusses quality control of spectacles. It defines quality as the features and characteristics that satisfy customer needs. Quality control is a management system that coordinates quality development, maintenance, and improvement across design and manufacturing departments. This ensures economical production and customer satisfaction. For spectacles, quality control checks the power, axis, centration, material, tint, prism, lens surfaces and segments, and tests for parallelism using a flat surface. It also checks rimless frame alignment and verifies lens segments in bifocals.
The document discusses ptosis crutches, which are used in eyeglasses for people with drooping eyelids. It provides the following key points:
- Ptosis crutches are formed wires mounted behind and parallel to the upper eye wire of glasses to support the skin of the upper eyelid and prevent it from drooping closed.
- The crutch is custom formed to the shape and contour of each individual's eye using stainless steel wire.
- Opticians take precise measurements to enable the eyelids to remain open in a relaxed state while still allowing the wearer to blink and close their lids when needed.
This document discusses different types of special purpose frames. It describes frames that hold supplementary lenses outside the main frame, frames that contain cells to hold additional lenses behind the prescription, and folding frames with hinges at the bridge and temples to reduce the frame size. It also covers frames with extensions to support the lower eyelid, trial frames without temples, monocular frames that allow viewing through one lens at a time, and frames with flip-down lenses for reading or sunglasses.
Dispensing glasses PPT for O.A. 2nd year Vinitkumar MJ
This document discusses frame and lens selection based on occupation and age. Key factors in frame selection include comfort, appearance, safety, and suitability for the person's occupation and lifestyle. Different occupations require consideration of visual needs, hazards, and working conditions. Frame material, size, and lens material should be chosen accordingly. For example, plastic frames and polycarbonate lenses are recommended for drivers and industrial or sports workers due to safety concerns. Progressive or multifocal lenses may be suitable for various occupations requiring vision at multiple distances.
The Hess screen test involves presenting lights in different positions of gaze on a screen and having the patient superimpose lights while viewing through colored lenses to dissociate the eyes. This allows evaluation of eye muscle function and detection of underaction or overaction. Key details include:
- The Hess screen contains lights indicating positions of gaze and is viewed through red-green lenses to dissociate the eyes.
- The procedure involves illuminating lights and having the patient superimpose them while viewing through the lenses.
- Interpretation of the plotted results can detect muscle underaction or overaction, indicating conditions such as nerve palsies or restrictions in eye movement.
This document discusses corneal curvature, thickness, and keratometry. It provides normal values for the cornea, including thickness, diameter, radius of curvature, and refractive index. Keratometry is defined as the measurement of the cornea. It is used to determine corneal curvature, astigmatism, and distortions. The document describes the optical principles and procedure for taking keratometry measurements. It discusses how to interpret the results and potential problems that can occur.
The document discusses the Jackson Cross Cylinder (JCC) test, which is used during refraction to detect and refine astigmatism. The JCC is a combination of two cylinders of equal strength but opposite signs, placed at right angles to each other. During the test, the JCC is held in different positions before the eye to see if there is a change in visual acuity. If a position is clearer, it indicates the axis of astigmatism. The test is then used to refine the axis and power of any astigmatic correction.
Reference point placement, multi focal height and blank size determination,Sahibzada H. Anjum Nadeem
1. Key factors in determining lens measurements include frame positioning, optical centering, prism placement, pantoscopic tilt, pupil height, and segment height.
2. The major reference point and optical center may differ depending on if prism is prescribed. Segment heights vary based on lens type but generally fall between 9-25mm from the bottom of the frame.
3. Pantoscopic tilt and vertex distance must be set properly based on pupil position and eye shape. Unequal segment heights can cause blurring and should be noted for the patient. Minimum blank size accounts for frame size and decentration.
Ophthalmic prisms are thin prisms with an apical angle of less than 10-15 degrees. They are used in refractive corrections and can be prescribed for conditions like strabismus. The orientation of a prism, whether base-in or base-out, affects how the eye perceives an object through the prism. Prism power can be calculated using formulas like Prentice's rule and decompounded or recombined as needed for a prescription.
Decentration of lenses can induce unwanted prism. The amount of induced prism depends on the distance of decentration from the optical center and the power of the lens. For plus lenses, the base of the induced prism is in the direction of decentration, while for minus lenses it is in the opposite direction. Prism power can be calculated using Prentice's rule. The induced prism from decentration can have effects on binocular vision and eye alignment. Careful centration of lenses is important for optimal vision and comfort.
This ppt presentation is about eyeglass frame styles that suit your face shape. The immense designs and creations of Lenspick.com have empowered the vision in developing different kinds of frame styles. This site consists a fabulous wide spectrum of frame style collections that best matches your face shape and magnifies your facial look. This presentation guides the wearers to pick out the right pair of eyeglasses fitted with a suitable frame style.
This document discusses progressive lenses, including their history, types, features, markings, fitting process, advantages, and disadvantages. It provides details on:
- The four main types of lenses - single vision, bifocals, trifocals, and progressive addition lenses.
- Key features of progressive lenses, including having multiple focal points that change continuously across the lens rather than distinct segments.
- Important temporary and permanent markings on progressive lenses used in fitting, including the fitting cross, distance reference circle, and lateral locator lines.
- The process of accurately relocating the fitting cross from temporary to permanent markings to ensure proper positioning over the pupil.
Segment height is a measurement needed when ordering progressive or bifocal glasses online. It refers to the vertical distance from the bottom of the lenses to the pupil. Knowing the segment height ensures the reading portion of progressive lenses is placed correctly. If the current frames are unavailable, measure similar frames owned to get the height and width for fitting purposes. The document then provides steps to accurately measure segment height with a ruler by aligning it with the bottom of the lens while facing a mirror.
This document discusses recumbent spectacles, which use reflecting prisms to enable people lying flat on their back to read. It describes how Andrew McKie Reid designed the first recumbent spectacles in 1935 using prisms with a 35 degree apical angle to bend vision almost 90 degrees. More recently, thin Fresnel prisms have been used as they are only 1mm thick and can be cut into any shape. The document discusses the optics, advantages and disadvantages of Fresnel prisms, as well as how to apply, clean and prescribe them.
This document discusses adjusting eyeglass frames to properly fit a patient's face. It covers adjusting the temple spread, positioning nose pads, checking the frame height and pantoscopic tilt. Temples should exert minimal pressure and have the bend just above the ear. Nose pads should rest halfway between the nose crest and inner eye, with the long diameter perpendicular to the floor. Proper adjustment ensures comfort and correct lens positioning.
Lens insertion for basic optical dispensingmikaelgirum
The document provides instructions for inserting lenses into plastic frames. It discusses heating the frame if needed, pre-shaping the eye wire to the lens curve, and inserting the lens by snapping the temporal edge in first and then the nasal edge. It describes checking that the lens is fully inserted and not twisted, as well as techniques for adjusting improperly inserted lenses.
This document describes the process of hand neutralization to determine the power of an unknown lens. Hand neutralization involves using a lens of known power to neutralize an unknown lens, where neutralization occurs when movement of the image through the lens is eliminated, indicating the lenses have cancelling powers. The steps include drawing a cross, determining lens orientation and optical center, neutralizing each meridian by finding the lens power that eliminates movement, recording the results as a power cross, and converting to a spherocylindrical formula.
This document discusses the different parts and types of eyeglass frames. It defines the frame as the portion that holds the lenses in front of the eyes. The key parts are identified as the bridge, eyewire, endpieces, hinges, temples, and nose pads. Different frame materials like plastic, metal, and nylon are described. Various bridge, endpiece, and temple designs are outlined, including saddle, modified saddle, keyhole, and turn back styles. Frame types such as half-eyes, rimless, and combination frames are also summarized.
This document discusses prisms and their effects on light refraction. It begins by explaining how a prism deflects light toward its base, causing the perceived image to shift toward the apex. Various prism properties are then defined, such as prism diopters used to measure deviation. The document also covers using prisms in lenses to create decentralization by shifting the optical center. It provides an example calculation for applying a prism to a plus lens to achieve a desired 5mm nasal decentralization. By adding a prism with a 2.2 prism diopter nasal base, the optical center is shifted as needed.
Polarized lenses block certain types of light waves to reduce glare. They work by only allowing vertically polarized light to enter the eye, blocking out horizontally polarized light that causes glare when reflected off smooth surfaces like water or roads. Polarized lenses come in various colors and are useful for activities like driving, boating, and photography by improving contrast and reducing eye strain from glare. While effective at reducing most types of glare, polarized lenses have some limitations like not working as well with snow glare and possibly distorting displays.
This presentation is prepared in the process of me teaching Visual Optics for graduate level optometry students. It narrates the type, clinical manifestations, clinical assessment and treatment of Aniseikonia.
This document discusses aspheric lenses. It begins with a brief history of aspheric lens development from 1909 to 1980. It then covers terminology, the introduction of aspheric lenses which aim to reduce optical aberrations compared to spherical lenses. The document discusses various aspheric lens designs and how they can reduce peripheral aberrations and make lenses thinner. It also covers measuring aspheric lenses, uses of aspheric lenses, and benefits such as reduction of oblique astigmatism and thinner lens designs.
This document discusses quality control of spectacles. It defines quality as the features and characteristics that satisfy customer needs. Quality control is a management system that coordinates quality development, maintenance, and improvement across design and manufacturing departments. This ensures economical production and customer satisfaction. For spectacles, quality control checks the power, axis, centration, material, tint, prism, lens surfaces and segments, and tests for parallelism using a flat surface. It also checks rimless frame alignment and verifies lens segments in bifocals.
The document discusses ptosis crutches, which are used in eyeglasses for people with drooping eyelids. It provides the following key points:
- Ptosis crutches are formed wires mounted behind and parallel to the upper eye wire of glasses to support the skin of the upper eyelid and prevent it from drooping closed.
- The crutch is custom formed to the shape and contour of each individual's eye using stainless steel wire.
- Opticians take precise measurements to enable the eyelids to remain open in a relaxed state while still allowing the wearer to blink and close their lids when needed.
This document discusses different types of special purpose frames. It describes frames that hold supplementary lenses outside the main frame, frames that contain cells to hold additional lenses behind the prescription, and folding frames with hinges at the bridge and temples to reduce the frame size. It also covers frames with extensions to support the lower eyelid, trial frames without temples, monocular frames that allow viewing through one lens at a time, and frames with flip-down lenses for reading or sunglasses.
Dispensing glasses PPT for O.A. 2nd year Vinitkumar MJ
This document discusses frame and lens selection based on occupation and age. Key factors in frame selection include comfort, appearance, safety, and suitability for the person's occupation and lifestyle. Different occupations require consideration of visual needs, hazards, and working conditions. Frame material, size, and lens material should be chosen accordingly. For example, plastic frames and polycarbonate lenses are recommended for drivers and industrial or sports workers due to safety concerns. Progressive or multifocal lenses may be suitable for various occupations requiring vision at multiple distances.
The Hess screen test involves presenting lights in different positions of gaze on a screen and having the patient superimpose lights while viewing through colored lenses to dissociate the eyes. This allows evaluation of eye muscle function and detection of underaction or overaction. Key details include:
- The Hess screen contains lights indicating positions of gaze and is viewed through red-green lenses to dissociate the eyes.
- The procedure involves illuminating lights and having the patient superimpose them while viewing through the lenses.
- Interpretation of the plotted results can detect muscle underaction or overaction, indicating conditions such as nerve palsies or restrictions in eye movement.
This document discusses corneal curvature, thickness, and keratometry. It provides normal values for the cornea, including thickness, diameter, radius of curvature, and refractive index. Keratometry is defined as the measurement of the cornea. It is used to determine corneal curvature, astigmatism, and distortions. The document describes the optical principles and procedure for taking keratometry measurements. It discusses how to interpret the results and potential problems that can occur.
The document discusses the Jackson Cross Cylinder (JCC) test, which is used during refraction to detect and refine astigmatism. The JCC is a combination of two cylinders of equal strength but opposite signs, placed at right angles to each other. During the test, the JCC is held in different positions before the eye to see if there is a change in visual acuity. If a position is clearer, it indicates the axis of astigmatism. The test is then used to refine the axis and power of any astigmatic correction.
Reference point placement, multi focal height and blank size determination,Sahibzada H. Anjum Nadeem
1. Key factors in determining lens measurements include frame positioning, optical centering, prism placement, pantoscopic tilt, pupil height, and segment height.
2. The major reference point and optical center may differ depending on if prism is prescribed. Segment heights vary based on lens type but generally fall between 9-25mm from the bottom of the frame.
3. Pantoscopic tilt and vertex distance must be set properly based on pupil position and eye shape. Unequal segment heights can cause blurring and should be noted for the patient. Minimum blank size accounts for frame size and decentration.
Ophthalmic prisms are thin prisms with an apical angle of less than 10-15 degrees. They are used in refractive corrections and can be prescribed for conditions like strabismus. The orientation of a prism, whether base-in or base-out, affects how the eye perceives an object through the prism. Prism power can be calculated using formulas like Prentice's rule and decompounded or recombined as needed for a prescription.
Decentration of lenses can induce unwanted prism. The amount of induced prism depends on the distance of decentration from the optical center and the power of the lens. For plus lenses, the base of the induced prism is in the direction of decentration, while for minus lenses it is in the opposite direction. Prism power can be calculated using Prentice's rule. The induced prism from decentration can have effects on binocular vision and eye alignment. Careful centration of lenses is important for optimal vision and comfort.
This ppt presentation is about eyeglass frame styles that suit your face shape. The immense designs and creations of Lenspick.com have empowered the vision in developing different kinds of frame styles. This site consists a fabulous wide spectrum of frame style collections that best matches your face shape and magnifies your facial look. This presentation guides the wearers to pick out the right pair of eyeglasses fitted with a suitable frame style.
This document discusses progressive lenses, including their history, types, features, markings, fitting process, advantages, and disadvantages. It provides details on:
- The four main types of lenses - single vision, bifocals, trifocals, and progressive addition lenses.
- Key features of progressive lenses, including having multiple focal points that change continuously across the lens rather than distinct segments.
- Important temporary and permanent markings on progressive lenses used in fitting, including the fitting cross, distance reference circle, and lateral locator lines.
- The process of accurately relocating the fitting cross from temporary to permanent markings to ensure proper positioning over the pupil.
Segment height is a measurement needed when ordering progressive or bifocal glasses online. It refers to the vertical distance from the bottom of the lenses to the pupil. Knowing the segment height ensures the reading portion of progressive lenses is placed correctly. If the current frames are unavailable, measure similar frames owned to get the height and width for fitting purposes. The document then provides steps to accurately measure segment height with a ruler by aligning it with the bottom of the lens while facing a mirror.
This document discusses recumbent spectacles, which use reflecting prisms to enable people lying flat on their back to read. It describes how Andrew McKie Reid designed the first recumbent spectacles in 1935 using prisms with a 35 degree apical angle to bend vision almost 90 degrees. More recently, thin Fresnel prisms have been used as they are only 1mm thick and can be cut into any shape. The document discusses the optics, advantages and disadvantages of Fresnel prisms, as well as how to apply, clean and prescribe them.
This document discusses adjusting eyeglass frames to properly fit a patient's face. It covers adjusting the temple spread, positioning nose pads, checking the frame height and pantoscopic tilt. Temples should exert minimal pressure and have the bend just above the ear. Nose pads should rest halfway between the nose crest and inner eye, with the long diameter perpendicular to the floor. Proper adjustment ensures comfort and correct lens positioning.
Lens insertion for basic optical dispensingmikaelgirum
The document provides instructions for inserting lenses into plastic frames. It discusses heating the frame if needed, pre-shaping the eye wire to the lens curve, and inserting the lens by snapping the temporal edge in first and then the nasal edge. It describes checking that the lens is fully inserted and not twisted, as well as techniques for adjusting improperly inserted lenses.
Orientation jaw relation 4 / dental implant courses by Indian dental academy Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
This document discusses the use of a face bow in dentistry. It begins by classifying jaw relations and defining important concepts like transverse axis and retruded contact position. It then describes the components and use of different types of face bows, including kinematic and arbitrary face bows. Key reference points are also outlined, such as orbitale and camper's plane. The document concludes by discussing the importance of using a face bow to accurately transfer the spatial relationship of jaws to an articulator.
This document discusses the use of a facebow to transfer jaw orientation from a patient to an articulator. It begins by explaining the importance of recording jaw orientation and its relationship to the skull. It then defines orientation jaw relation and describes how a facebow is used to locate three reference points (condylar centers and infraorbital notch) to establish the maxilla's angle. The document discusses arbitrary and kinematic facebows and their parts. It provides steps for making a facebow recording and transferring it to mount the dental cast on an articulator.
This document provides information on how to use a lensmeter and keratometer to measure eyeglass lenses and corneal curvature. It describes the parts and functions of a lensmeter, including how to focus the eyepiece, position lenses, and measure sphere, cylinder, and prism powers. It also outlines the Javal-Schiotz and von Helmholtz methods used in keratometry to measure corneal curvature based on the shadow cast by the cornea. Step-by-step instructions are provided for using both devices to obtain measurements of patients' lenses and corneas.
The document discusses factors to consider when selecting frames for a patient's prescription lenses. It describes how frame selection can affect the apparent length and width of the face, as well as facial balance and features. Frame shape, size, color, thickness, and bridge design were some of the key factors discussed in relation to complementing different facial structures. The document emphasizes matching frames to the individual's facial characteristics for optimal aesthetic results.
1. model #8500 articulator /certified fixed orthodontic courses by Indian den...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
This document discusses bracket positioning gauges and techniques for proper bracket placement. It describes:
1. Types of bracket positioning gauges including star shaped and straight rod shaped gauges.
2. Parts of gauges including the holding arm, tooth supporting arm, and slot supporting arm.
3. Correct positioning of gauges which should be perpendicular to the tooth surface to ensure accurate bracket height.
4. Techniques for placing brackets on individual tooth types from different clinician positions to accurately assess bracket alignment.
A surveyor is used to analyze dental casts and determine the optimal path of insertion for a dental prosthesis. Key steps in surveying include:
1. Surveying the diagnostic cast to determine the best tilt and path of insertion based on factors like undercuts, interferences, aesthetics and guiding planes.
2. Marking "tripod marks" on the cast to allow repositioning it on the surveyor in the same orientation.
3. Using the determined path of insertion and tripod marks to guide procedures like wax pattern contouring, crown shaping, and placement of attachments and rests.
The surveyor helps optimize retention, stability, and aesthetics of the prosthesis during its
Articulato /certified fixed orthodontic courses by Indian dental academy Indian dental academy
The document discusses the process of mounting dental casts onto an articulator using a facebow. It involves positioning the nasion relator on the facebow crossbar, determining condyle width and angulation, transferring the facebow registration to the articulator, mounting the upper dental cast, and adjusting the incisal guide pin and table. Guidelines are provided on positioning the lower dental cast in centric relation and adjusting condylar guidance for lateral excursions based on registrations from a human skull. The articulator movements are traced and compared to different adjustment settings.
Facebow in orthodontics /certified fixed orthodontic courses by Indian dental...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
The document provides information about facebows, including:
1. It defines a facebow as a device used to record the relationship between the jaws and temporomandibular joints and orient dental casts on an articulator.
2. The main parts of a facebow are described as the U-shaped frame, condylar rods, bite fork, and locking device.
3. Facebows are classified as arbitrary or kinematic, with arbitrary facebows approximating but not precisely locating the hinge axis.
This document discusses different types of facebows used to transfer the spatial relationship of the maxilla to an articulator. It describes arbitrary, kinematic/hinge, and fascia type facebows. The kinematic facebow locates the true hinge axis most accurately within 5 mm. Arbitrary facebows use approximate reference points which can introduce errors. The document also outlines the parts of a facebow including the U-shaped frame, condylar rods, bite fork, locking device, and orbital pointer pin. It emphasizes the importance of using a facebow to accurately capture the patient's hinge axis for producing biologically acceptable restorations.
This document provides an overview of orientation relations and facebows. It defines key terms like jaw relation, orientation relation, and facebow. It describes the transverse hinge axis and sagittal plane. It discusses different types of facebows like kinematic, arbitrary, and earpiece facebows. It covers the procedure for taking a facebow record and potential errors. The document also reviews literature on controversies around locating the hinge axis and accuracy of arbitrary vs kinematic facebows. It provides a brief history of the development of facebow instruments over time.
This document discusses various concepts related to determining reference points, measuring for lenses, and selecting blank sizes. It covers positioning frames properly, centering single vision lenses, calculating prism effects, measuring multifocal segment heights, determining pantoscopic tilt, and finding the minimum blank size based on factors like effective diameter and decentration. Proper frame fitting and reference point placement are essential for accurate lens measurements and specifications.
Vertical force consideration in differential space closure /certified fixed o...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
Indian Dental Academy: will be one of the most relevant and exciting training
center with best faculty and flexible training programs for dental
professionals who wish to advance in their dental practice,Offers certified
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Prosthetic Dentistry, Periodontics and General Dentistry.
Semelhante a standard frame alignment for basic frame adgustment (20)
The document discusses various parts and types of eyeglass frames. It describes the basic components of frames including the front, hinges, temples, bridges and end pieces. It outlines different frame constructions such as plastic, metal, nylon cord and combination frames. It also discusses specialized frame types like half-eyes, rimless and semi-rimless frames. The document provides details on materials used in frames like cellulose acetate, propionate, nylon and carbon fiber.
This document discusses eye optics and refractive errors. It provides 3 case studies: a 14-year-old boy unable to see the blackboard, a 51-year-old man with difficulty reading the newspaper, and a 6-year-old girl who squints when looking farther than 2 feet away. The objectives are to understand eye optics, visual acuity assessment, common refractive errors, and color perception assessment. Key refractive errors like myopia, hyperopia, presbyopia, and astigmatism are explained in terms of etiology, presentation, diagnosis, and treatment.
Keratometry is a technique used to measure the curvature of the cornea. It works by analyzing the reflection of light off the cornea's convex surface. Keratometry can determine the radius of curvature and refractive power of the cornea. This information is useful for contact lens fitting and calculating intraocular lens power for cataract surgery. Modern keratometers automate the measurement process for improved accuracy and efficiency.
The document discusses various risks and complications that can arise from soft contact lens wear, including hypoxia, desiccation, deposit buildup, mechanical issues, and inflammatory responses. It covers specific conditions like epithelial edema, stromal edema, microcysts, vascularization, polymegethism, endothelial blebs, dry eye, contact lens papillary conjunctivitis, contact lens superior limbic keratoconjunctivitis, acute red eye, sterile infiltrates and ulcers, and preservative allergies and sensitivities. Potential causes, symptoms, diagnoses, and treatment approaches are provided for each condition.
This document discusses cataracts, including their classification, causes, symptoms, diagnosis, and treatment. It notes that cataracts are the opacification and clouding of the lens of the eye. They are classified morphologically or etiologically. Senile cataracts related to aging affect over 90% of people by age 70 and are the most common type. Examination involves assessing visual acuity, eye pressure, and examining the anterior segment and fundus. Treatment options include glasses initially, but surgery such as phacoemulsification is often needed for more advanced cases. Complications of surgery can include inflammation, edema, and retinal detachment.
Myopia, also known as nearsightedness, is a refractive error where light rays focus in front of the retina rather than directly on it. There are several types of myopia including simple/developmental myopia, pathological myopia, and acquired myopia. Treatment options include optical correction using concave lenses, surgical options like LASIK, and general measures like visual hygiene and a balanced diet. Prognosis depends on the type and severity of myopia.
Refractive error is a condition where the eye fails to form a clear image on the retina when light enters from infinity and accommodation is relaxed. The major types of refractive error are myopia, hyperopia, and astigmatism. Uncorrected refractive error is a leading cause of blindness worldwide, affecting over 2 billion people with 88.4 million having uncorrected refractive error. Children in urban areas and people over age 50 are most affected. The main reasons for high rates of uncorrected refractive error are lack of vision testing, limited refractive services, and affordability and cultural issues regarding corrective devices. Comprehensive community-level refractive services and school vision testing programs are important strategies to address this major global cause of visual impairment.
This document discusses visual impairment and blindness in Ethiopia. It identifies the main causes of visual impairment as cataract, uncorrected refractive error, glaucoma, corneal opacities, and diabetic retinopathy. For childhood blindness, the leading causes are uncorrected refractive error, cataract, retinopathy of prematurity, trauma, trachoma, and xerophthalmia. The document also explains how visual acuity is measured using a Snellen chart and expressing the results as a fraction where the top number indicates the test distance and the bottom number is the equivalent distance for a person with normal vision.
This document discusses anti-reflective coatings. It begins by describing their applications in corrective lenses and photolithography. It then outlines different types of coatings, including index-matching, single-layer interference, multi-layer interference, absorbing, moth eye, and circular polarizers. The document also covers the theory behind how reflection and interference coatings work to reduce reflection at surfaces. Key points include using layers of different refractive indices to destructively interfere reflected beams while constructively interfering transmitted beams.
1. The document discusses properties of light including its nature as electromagnetic radiation, its movement as waves, and its interaction with materials through transmission, reflection, absorption, and scattering.
2. Visual functions like visual acuity, dark adaptation, visual fields, and color vision are assessed clinically and their development and measurement are described.
3. Methods for measuring visual acuity both qualitatively and quantitatively are outlined, including grating acuity, Vernier acuity, and various acuity tests appropriate for different populations. Factors that affect acuity measurements like crowding effects are also addressed.
This document provides guidelines for routine refraction procedures and prescription writing. It discusses evaluating the patient history and vision, performing subjective and objective refraction tests, and guidelines for prescribing corrections for myopia, hyperopia, astigmatism, and presbyopia. It also addresses some common refraction cases involving these conditions and provides guidance on determining the appropriate correction or next steps.
1) Eye movements can be translatory (sideways, up/down, forward/backward) or rotary (around vertical, horizontal, or anteroposterior axes). Rotary movements occur around a center of rotation within the eyeball, which does not remain fixed.
2) Eye movements are governed by Donders' Law, Listing's Laws, Sherrington's Law of Reciprocal Innervation, and Hering's Law of Equal Innervation. These laws describe how eye movements maintain a consistent retinal image orientation and involve coordinated contraction/relaxation of agonist and antagonist muscles between the two eyes.
3) Eye movements are categorized as versions (simultaneous movements of both eyes),
Vision disorders are common in children and can negatively impact development if left untreated. A comprehensive eye exam evaluates vision, eye alignment and tracking, focusing ability, and screens for conditions like nearsightedness and lazy eye. Exams are important because many issues have no obvious symptoms. Screenings miss up to 1/3 of problems and may lead to misdiagnoses. Comprehensive exams are recommended at ages 6 months, 3 years, before school, and every 2 years thereafter to catch issues early for best outcomes. Bringing an infant for an exam requires preparing them to be well-rested and not distressed.
This document discusses vision syndrome, also known as binocular, accommodative, and oculomotor dysfunction (BAOD). BAOD is a common condition that affects reading and learning and often goes undetected on standard vision screenings. It involves dysfunctions in binocular control, accommodation, and oculomotor control. The document outlines signs and symptoms of BAOD, provides prevalence data, and recommends doctors evaluate for BAOD in patients with learning difficulties and refer for office-based vision therapy if needed.
Binocular vision develops gradually in infants, from following light monocularly at 2-3 weeks to binocularly at 6 weeks to 6 months. By 6 months, accommodation has developed but lags behind convergence. Sensory fusion blends monocular images into a single image, while motor fusion maintains eye alignment. Binocular vision provides advantages like single vision, stereopsis, and an enlarged visual field. Normal binocular vision requires clear visual axes, sensory fusion, and motor fusion.
The document discusses preoperative evaluation and measurements for cataract surgery, including biometry. It covers evaluating the general health and ocular history of the patient, performing visual acuity testing, refraction, and other objective tests. It then describes methods of measuring the eye, including A-scan biometry to determine axial length using ultrasound, and optical biometry using light waves. Factors that can influence biometry measurements and techniques like keratometry are also discussed. The document concludes by covering intraocular lens power calculation and selection, noting the importance of accurate measurements and various generation of formulas used.
Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
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Adhd Medication Shortage Uk - trinexpharmacy.comreignlana06
The UK is currently facing a Adhd Medication Shortage Uk, which has left many patients and their families grappling with uncertainty and frustration. ADHD, or Attention Deficit Hyperactivity Disorder, is a chronic condition that requires consistent medication to manage effectively. This shortage has highlighted the critical role these medications play in the daily lives of those affected by ADHD. Contact : +1 (747) 209 – 3649 E-mail : sales@trinexpharmacy.com
Our backs are like superheroes, holding us up and helping us move around. But sometimes, even superheroes can get hurt. That’s where slip discs come in.
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotesPsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
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Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
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2. STANDARD ALIGNMENT OR “TRUING” OF FRAMES
- adjusted to certain impersonal standards that are
independent of the type of face to which it is to be fitted.
- The best time to pre adjust is when the prescription is being
verified.
3. “Truing” spectacles is a good starting point for adjusting them,
especially spectacles that have been worn for a long time
without recent adjustment.
A general rule for standard alignment is to begin with the bridge,
then work with the end pieces, and handle the temples last.
4. • Obviously, changes made in one part of a frame may influence
the alignment in another part.
• Bending the bridge, for example, may change the relationship
of the temples.
• Handling the bridge first, and the other parts in order, helps to
eliminate having to go back and realign parts.
5. Adjustable plastic frames must almost always be heated to be
aligned.
Metal frames and parts do not require heating, except for metal
parts that are covered with plastic.
6. Standard Alignment of Plastic Frames
HEATING THE FRAME
Standard plastic frames must be heated for any alignment.
Standard procedure for adjusting the frame should be followed,
beginning with the bridge.
Only that area of the frame requiring adjustment should be
heated to avoid the possibility of disturbing an aligned area by
mistake.
7.
8. THE BRIDGE
Readjusting the lenses to their proper planes is accomplished by
first heating the bridge area, then grasping the frame by the lens
areas and adjusting according to the correction desired.
When using a salt pan to heat the bridge, stir the salt in the pan
and form it into a centrally located peak running across the pan.
9. • Place the frame in the pan, temples up, and draw the bridge
through the peak of the salt mound.
• Repeat until the bridge is pliable enough to be bent.
10. Move the bridge through the hot air stream until it becomes
pliable.
If one lens is higher than the other, they are said to be out of
horizontal alignment.
If one lens appears to be farther forward or backward than the
other, they are said to be out of vertical alignment.
11. Horizontal Alignment
It is not easy to check for horizontal alignment of a plastic frame
because there are not always clear reference points.
To check for horizontal alignment, place a ruler or straight edge
across the back of the frame at the top of the pads.
Both endpieces should be equidistant.
Causes: Rotated Lens
Skewed Bridge
12. Vertical Alignment (Four-Point Touch)
To check place a ruler or straight edge so that its edge goes
across the inside of the entire front of the spectacles below the
nose pad area.
Theoretically the frame eyewire should touch at four points on
the ruler
13. Face Form
Face form or wraparound is when the frame front is just slightly
rounded to the form of the face.
Frames with face form will not conform to the four point touch
test, but must be symmetrical nonetheless.
The temporal sides of the eyewires should touch, and the nasal
sides should be equidistant from the ruler.
14. Too much face form would be evident if the two nasal eye wires
are a great distance from the ruler.
The remedy for either too much or too little face form is to alter
the bridge. First warm then grasp the frame by the lenses and
eye wires with thumbs on the inside and fingers on the outside.
Bend the bridge by turning the lenses inward or outward.
15. X-ing
The frame front may be twisted so that the planes of the two
lenses are out of coincidence with each other.
This is called Xing because the eye wires of the frame front form
an X when viewed from the side.
X-ing causes the temples to be out of line with each other.
16. • When ever the temples do not appear parallel, the frame
should first be examined for X-ing before other methods of
realigning the temples are tried.
• X-ing is corrected by grasping the eye wires and rotating the
hands in opposing directions until the planes of the lenses are
parallel.
17. Variant Planes
Another form of vertical misalignment is when the lens planes
are variant, or out of coplanar alignment.
the lens planes are parallel, but one lens is farther forward than
the other.
push the entire eyewire away from you on one side, and pull it
toward you on the other side, all the while keeping both lens
planes parallel to each other.
18. THE TEMPLES
The open temple spread is checked first because the
adjustments may affect the end pieces.
After this, temple parallelism is considered, followed by
alignment of the temple ends.
Finally the temple fold angle is corrected.
.
19. Open Temple Spread
The open temple spread, or let-back, is that angle that each open
temple forms in relationship to the front of the frame.
To afford a true picture of the temple spread initially, the temple
shafts must be straight.
Any curve to the temple shaft should be eliminated by heating
the temple and straightening it with the hands.
It is the normal condition of the temple to be opened out
slightly farther than a 90-degree angle; usually 94-95 degrees.
20. Temple Parallelism
For frames to be in standard alignment, the temples need to be
parallel to one another and should not be angled down more than
the other.
When looking at the glasses from the side, the angles the temples
make with the frame front determine temple parallelism.
Pantoscopic angle is the angle the frame front deviates from the
vertical when the glasses are held with the temples horizontal.
Viewing the frames from the side, when the lower rims of the frame
front are closer to the face than are the upper rims.
21. • A proper pantoscopic angle may vary from as little as 4
degrees up to 18 degrees.
• If the glasses were to be adjusted so that the lower rims are
tilted outward from the face, the glasses are said to have
“retroscopic” instead of pantoscopic tilt.
• In any case, to test whether or not the temples are parallel,
position the glasses upside-down on a flat surface with the
temples open.
22. if both temples sit flat or if one temple is not touching the flat
surface.
If it is difficult to tell, first touch one temple and then the other
to see if the frame wobbles back and forth or if it sits solidly.
This procedure is known as the flat surface touch test. If the
frame wobbles, it needs correction or it will sit on the face at an
angle.
23. Temple-Fold Angle
The final alignment step is to fold the temples to the closed
position and observe the angle formed as the temples cross.
The temples should fold so that they are parallel to one another
or form slight angles from parallel.
These angles should be symmetrical and should cross each other
exactly in the center of the frame, in line with the center of the
bridge.
Proper adjustment to this confi guration permits the spectacle to
easily fit into a standard case for glasses.
24. Standard Alignment of Metal Frames
The primary difference lies in the methods of manipulation used
to bring the frame into alignment and the presence of adjustable
nose pads.
Metal frames require heating only in those places where plastic
coats the metal.
All other bends are done “cold.” Pliers are used for the majority
of adjustments.
25. THE BRIDGE
Horizontal Alignment
To check for horizontal alignment of a metal frame, place a ruler
or straight edge across the front of the frame at the point of
attachment of the pad arms.
In most frames, the endpieces will be considerably higher than
the level of the pad arms, making the horizontal alignment
judgment difficult.
The end pieces should be equidistant from the ruler.
Causes : Rotated Lens
Skewed Bridge
26. Vertical Alignment (Four-Point Touch)
As when performing the four-point touch test with plastic
frames, a ruler or straight edge is necessary to determine
whether or not the frame is in alignment.
Metal frame construction is so varied, however, that establishing
a four-point touch when straddling the inner parts of the frame
eye wires is more often impossible than possible.
The test is used to analyze the symmetry of the frame front.
27. Face Form
Metal frames are usually designed with face form, especially in the
larger eye sizes.
When checking vertical alignment, there are two questions to keep
in mind:
1. Does the frame have a four-point touch or a face form curve?
2. If the frame has face form, are the two nasal eye wires
equidistant from the ruler or is one farther from it than the other?
28. Standard Alignment of Nose pads
final adjustment of the pads will vary extensively with the
individual shape and flare of the nose of the intended wearer.
There are three basic angles that are used for reference when
aligning nose pads.
These are the frontal, splay, and vertical angles.
29. FRONTAL ANGLE (VIEWED FROM THE FRONT)
The frontal angle of the nose pads refers to the vertical position of the
pads in relation to each other when viewed from the front.
The tops of the pads should be closer together than the bottoms,
angling in toward each other approximately 20 degrees from a true
vertical.
Most pads can be “rocked” about a swivel joint. The pads should be
slanted for the frontal angle by the same amount.
30. Pad Spacing
While viewing the frontal angle, observe the amount of space
between the eye wires and pads.
Both pads should be equidistant from their respective eye wires.
An estimated ideal position is for the face of the pads to appear
approximately 1 mm closer to the nose than the eye wire itself.
31. Pad Height
A third point of observation is whether or not both pads occupy
the same horizontal plane.
If one pad appears higher than the other, the pad arm may be
bent upward.
It is essential that both pads be in identical rocking positions
because if one is erect and one is slanted, their heights may
appear dissimilar.
32. SPLAY ANGLE
This difference then between the back and front edges of each
pad, viewed from the top or the bottom, is the splay angle.
For initial alignment, a splay angle of 25 to 30 degrees is
satisfactory and may be achieved through the use of the pad-
adjusting pliers.
33. VERTICAL ANGLE (VIEWED FROM THE SIDE)
The angle most often neglected in the
standard alignment of nose pads is the
vertical angle.
This angle is especially important in
ensuring proper weight distribution
under the pad.
Ideally the longitudinal (top to
bottom) axis of the pad face is in
contact with the nose surface in the
direction of gravity.
34. Standard Alignment of Rimless Eyewear
RIMLESS CONSTRUCTION AND LENS MATERIALS
Rimless are still more difficult to adjust than plastic and metal
frames.
Newer mountings use a variety of methods to give extra stability
to the mounting.
In the past, the lens was held in place with one hole nasally and
one hole temporally.
Now there may be more than one hole, or a hole and an edge
notch used in combination.
35. Appropriate Lens Materials
If appropriate lens materials are used for rimless mountings, lens
chipping is vastly reduced.
the best lens materials for rimless mountings are Trivex and
polycarbonate.
36. ALIGNING THE BRIDGE
Whereas the bridge or pad arm origins and the end pieces serve
as the line of reference for frames, the mounting line serves as a
line of reference for rimless mountings.
The mounting line is defined as “the line which passes through
the points on the eye wires or straps at which the pad arms are
attached.
The end pieces may be attached on this line, or as may be the
case, above or below this line.
37. RIMLESS ADJUSTMENTS
Rimless Nose pad Alignment
The chief distinction in technique is
that the bending of the pad arms
should not be attempted unless the
base of the pad arm is sufficiently
supported to prevent stress on the
mounting point and lens.
This support can be given by holding
the mounting point with rimless
bracing pliers while adjusting the pads
with pad adjusting pliers.
39. Workshop practice guideline
1. Identify lens material.
a. glass b. plastic
2. Identify frame material.
a. plastic( different type) b. metal (different type)
3. Measure spherical SVL? (at least 5 lenses)
4. Measure sphero cyl SVL? ( at least 5 lenses)
5. Measure bifocals? ( at least 3 lenses )
6. Measure progressives? ( at least 2 lenses )
7. Frame selectin, alignment and adjustment?