Photoelectric sensor introduction types advantages-disadvantages application

1. Photoelectric sensors
Presented by:
Darshil Shah
IU1241090051

2. Content
 What is photoelectric sensor?
 Sensing mode
 Working, Advantages & Disadvantages of sensing
modes
 Application

3. What is photoelectric sensor?
• A photoelectric sensor, or photo eye, is a device used to
detect the distance, absence, or presence of an object by
using a light transmitter, often infrared, and a photoelectric
receiver
• The output signal can be analog or digital and is often
internally modified with timing logic, scaling, or other signal
processing prior to output

4. Sensing modes
 Through beam
 Retro-reflective
 Diffused beam

5. Through-beam
 Working:
The transmitter and receiver of the thru beam sensor are
housed in different cases that are separated from each other.
The Emitter (E) transmits directly to the receiver (R). If an
object (O) interrupts the light beam, the receiver voltage
drops and the switching function is initiated
E R
O

6.  Advantages :
1. Most accurate.
2. Longest sensing range.
3. Very reliable.
 Disadvantages:
1. Must install at two points on system: emitter and receiver.
2. Costly - must purchase both emitter and receiver.

7. Retro-Reflective
 Working:
The retro-reflective sensor contains the emitter and receiver
in a single housing. The light from the transmitter is beamed
back from a reflector to the receiver. If the beam of light is
interrupted, the switching function is initiated

8.  Advantages:
1. Cost less
2. Sensing range better and Very reliable
 Disadvantages:
1. Must install at two points on system: sensor and reflector
2. Slightly more costly than diffuse
3. Sensing range less than through-beam

9. Diffused-beam
 Working:
The structure of the diffuse mode sensor is based on the
same principle as a retro-reflective sensor. It does not have a
reflector, however. Instead, the light reflected from the
recorded object is evaluated by the receiver.

10.  Advantages:
1. Only install at one point
2. Cost less than through-beam or reflective
 Disadvantages:
1. Less accurate than through- beam or reflective
2. More setup time involved

11. Applications
1. Piled up ice cream cups
Through beam laser sensor detects piled up ice cream cups.
Small spot size of laser finds slight changes in tallness.

12. 2. Through beam laser sensors we use water detection detects
whether transparent bottle is filled with clear liquid or not

13. 3. Defects seal on instillation bags.
When it's sealed, diffuse sensor detects upper edge of the bag
and finds its distortion

14. 4. If flowing can is fallen down, some sensor does not detect
anything and find trouble.
As Reflective laser sensor, stable detection without
influences from designed print and glaze can be available.

15. References
• www.sick.com
• www.balluff.com
• www.eaton.in
• www.bannerengineering.com
• www.automation.com
• www.rockwellautomation.com
• www.ia.omron.com