What is a Laser Sensor? Principle

A laser sensor is a very important technique used in electronics. As the name implies, it is a sensor that uses laser light or rays for sensing an object. It makes optics and photo electricity into pictures for working. As a transducer, it converts light energy into electrical energy. It is used in many industrial automation applications.

In this post, we will the concept of a laser sensor.

What is a Laser Sensor?

A laser is a focused beam of light. So, this sensor emits laser light in a small bright dot form. This beam is very fine and provides a great level of accuracy. Laser light is emitted from the sensor to the object which is to be sensed.

Light is reflected from the object back to the sensor. The sensor has an internal digital circuit that uses signal processing, to study light behavior.

That means, it calculates the time taken for the light to emit and then reflect back to the receiver. And as the laser light emission speed is fixed, it calculates the distance of the object from the sensor; based on speed and time.

The sensor then generates an electrical output corresponding to the distance sensed. This output can be digital or analog and can be further used as signal input for controllers or PLC. Thus, the laser sensor converts light energy into electrical energy.

Advantages of Laser

The following are the advantages of laser sensors.

It has a very high direction of the beam and a small divergence angle of light speed.
It has high levels of brightness.
The frequency width of the laser is 10 times smaller than ordinary light.
Precise measurement of length and is 1000 times purer than even the best monochromatic light source (krypton).
Its range can extend up to several kilometers.
It can be used for a wide variety of applications; ranging from measuring length to thickness and even the angle, length, eccentricity of inner and outer diameter, concentricity, and surface profile of a cylindrical shaped object.
You can get digital (NPN or PNP output contact) as well as analog (0-10 V DC or 4-20 mA) electrical output.
They work well in dusty conditions. The bright light of the laser sensor is not affected by other light sources. So, they can also be used even in direct sunlight.

Types of Laser Sensor

There are two types of laser sensors available. They are

Laser Displacement sensor
Laser Distance sensor

Applications of Laser Sensor

The following are the applications of laser sensors.

Comments

What is a Torbar? – Averaging Pitot Tubes

The Torbar is employed for flow measurement of liquids, gases, or steam in circular, square, or rectangular section ducts for large flow rates. The Torbar is an insertion type multi-port self-averaging primary sensor for flow measurement. Torbar TORBAR is a set of Pitot tubes mounted on a bar across the pipeline with no moving parts. An averaging Pitot tube is a technology, while TORBAR is a manufacturing brand name. There are several brands available in the market with VERABAR, ANNUBAR, etc. Averaging Pitot Tube Principle Purpose Averaging Pitot tube can be employed when the average velocity of the flow profile, rather than the velocity in a specific point in the cross-section is desired. Averaging Pitot Tubes Principle It measures the differential pressure between the static pressure tap and the tap of full pressure of a stream. Thus such magnitude of differential pressure is directly proportional to the square of the flow rate. Working The TORBAR is designed in such a way that ...

Ferrules and Cross Ferruling

Ferrules are identification labels provided for every wire terminations in an instrument, equipment, or electrical/instrumentation control panels. These tube-shaped sleeves can be inserted easily on each individual wire in a multi-core cable. In earlier days fixed digits/letters are used as ferrules, but now Instrumentation engineers/technicians prints out desired ferrules by using a ferrule printing machine. Typical Ferrule The numbers/ letters on the ferrules will be given as per the approved electrical hook up or loop diagrams. This helps technicians to easily identify a particular loop/wiring from a series of terminal blocks and to troubleshoot the desired terminal connection. Separate numbers on the ferrules distinguish the positive and negative polarities of wires, thus ensure the polarity protection of the instrument. Cross Ferruling As a wire is connected on its both ends, it is quite useful to use a cross reference method for wire identification. Unlike normal ferru...

Thermowell Insertion and Immersion Length

The thermowell is the industrial housing for temperature elements like RTD or thermocouple or temperature gauges. Thermowell is directly exposed to process fluid/media. Inside the thermowell, element/gauge is installed. Thermowell transfers the heat to the temperature element. Depending upon the element type, the fluid temperature can be known. So Thermowell protects the temperature element against harsh conditions and process fluid. It enables removal of the temperature element for replacement, repair, or testing without affecting the process system. Generally, thermowells are provided with all-temperature Elements like RTD or Thermocouple or temperature gauge. A few exceptions would be bearing RTD, skin type thermocouple, air duct thermometer, etc where thermowell is not applicable / required. When the thermowell assembly is inserted into the pipe, it is subjected to vibration. This vibration is caused by vortices to be generated alternately on either side of the thermowell. The...

TILI Automation

Search This Blog