Fiber Optic Sensor Selection Guide Part 2

Alright, so we have already covered single core, multi core, FEP sheated, high flex and armoured type of optical sensors. We are going to look into more.

Lets start with:

1. Heat Resistant Optical Sensor. In some places, the heat generated by machine can reach up to hundreds of degrees (more than enough to boil water). If normal optical sensors are used in places like this, the cladding will melt in seconds. The heat resistant optical sensors can withstand heat ranges from 212°F ~ 662°F.


2. Liquid Level Detection Optical Sensor. Just like it's name. It is used to detect liquid level. There are a few types of optical sensors which can be used to detect liquid level. If you wish to detect level without touching the liquid, then a clip type can be used, where the optical sensor is clipped at the external tube. Otherwise, use immerse type of optical sensor which require positioning (position the sensor at the desired level).
   



3. Space Saving Optical Sensors. For many application space is a concern and many machine makers and engineers tend to use normal optical sensors which actually cheaper. The usage of normal optical sensors at places like this cause a lot protrusion of the cable. Hence, it actually increase the chance to break it due to recklessness. Pictures will say a thousand words on this. As shown below, the pic on the right is mounted right angle which is actually protected by a nut. It actuallly reduce protrusion which lead to high maintenance of due to broken optical sensor head. There are many more space saving sensors out there. Flat type, miniature type, zero space..to name a few. Depending on the space constraint that you face, you can actually select from a wide range. Look for your supplier and ask for Space Saving optical sensor. It doesn't cost much anyway. But it saves you time and money in long run.
   



4. Transparent Target Detection Optical Sensors. The most common optical sensors used in various industries are reflective and thrubeam type. However, these two sensor actually have problem detecting clear transparent object. For a better detection of transparent object, a retro-reflective optical sensor is used. Retro-reflective optical sensors uses a reflector to complete the detection. The light beam penetrate the object and reflected by back the reflector. Through the reflection, the light beam actually passes through the transparent object twice, which actually creates much more difference of light received during absense and presence of object.



5. Area Beam Optical Sensor. Area beam optical sensor actually produce a considerably wide area for object detection. Normal optical sensor has a coverage of limited area of detection due to the relatively small straight line of emission. Because of this, objects to be detected must pass through at the same position every time. However, if area beam optical sensor is used, a greater tolerance of object position is possible. Sometime, vibration of machine itself caused the position of the object to be unpredictable.


6. Small Beam Spot Optical Sensor. Normal optical sensors has light dispersion of 60 degrees which made it almost impossible to detect minute object. Small beamspot optical sensors produce beamspot up to 0.1mm. For application such as pin counting or IC checking, this sensor will provide a very stable detection.

Thats about it for this post. Thanks for reading though.

Optical Sensor Selection Guide Part 1

Cheers.