The measurement of length is mostly based on the interference phenomenon of light waves, and its accuracy mainly depends on the monochromatic quality of light.The ideal light source is the laser, which is 100, 000 times purer than the best monochromatic light source (Krypton 86).Therefore, laser measuring long range and high precision.According to the optical principle, the relationship between the maximum detectable length L of monochromatic light and wavelength and line width is L= 2/.The maximum length can be measured with krypton -86 lamp is 38.5 cm, for longer objects need to be measured in sections to reduce the accuracy.If using he-Ne gas laser, the maximum can be measured tens of kilometers.Generally measured within a few meters, the accuracy can be up to 0.1 micron.
It works in the same way as a radio radar. After aiming a laser at a target, it measures its round trip time and multiplys the speed of light to get the round trip distance.Because of the advantages of laser, such as high directivity, high monochromator and high power, these laser can be used to measure the distance, determine the target orientation, improve the signal-to-noise ratio of the receiving system, and ensure the measurement accuracy
Using the triangle range principle, in C type frame, below the segmentation on a precision laser displacement sensor, the modulation of the laser is emitted by a laser hit the surface of the measured object, through to the linear CCD signal sampling processing, linear CCD camera in the analyte under the control of the synchronous control circuits to the distance between the C type frame, through the sensor data to calculate the thickness of the measured object in the middle.
In the Laser Doppler vibrational velocity meter,fd =2v/ lambda due to the roundtrip of light.The vibration is the vibration of the objects in the measurement by optical parts will be converted to the corresponding doppler frequency shift, and by the optical detector converts the frequency shift to electrical signals, then by circuit part after appropriate treatment to the doppler signal processor of the doppler frequency shift signal transformation for vibration velocity and the corresponding electrical signals, finally recorded on magnetic tape.The vibration is the wavelength for 6328 spots (┱) of he-ne laser, optical frequency modulation, using acousto-optic modulator with quartz crystal oscillator and power amplifier circuit as driving source of acousto-optic modulator, photoelectric detection, using photomultiplier tubes with frequency tracker to process the doppler signal.
It is also a laser velocity measurement method based on The Quito Doppler principle. The laser Doppler velocimeter is widely used, which can measure the wind tunnel airflow velocity, rocket fuel velocity, aircraft jet flow velocity, atmospheric wind speed and particle size and convergence velocity in chemical reactions, etc..
1. Dimension measurement: position identification of tiny parts;Whether there are parts on the conveyor belt monitoring;Detection of material overlap and cover;Manipulator position (tool center position) control;Device status detection;Device position detection (through holes);Monitoring of liquid level;Measurement of thickness;Vibration analysis;Collision test measurement;Automobile test and so on.
2. Thickness measurement of metal sheet and sheet: Laser sensor measures the thickness of metal sheet (sheet).Variations in thickness can help detect wrinkles, holes or overlaps to avoid machine failures.
3. Cylinder cylinder measurement: Angle, length, eccentricity of inner and outer diameters, conicity, concentricity and surface contour.
4. Length measurement: The measured component is placed on the conveyor belt at the specified position. The laser sensor detects the component and measures it at the same time with the triggered laser scanner to obtain the length of the component.
5. Check the uniformity: put several laser sensors in a line in the inclined direction of the workpiece movement to be measured, and output the measurement value directly through a sensor. In addition, a software can be used to calculate the measurement value and read out the result according to the signal or data.
6. Inspection of electronic components: two laser scanners are used to place the measured components between the two, and finally the data is read out through the sensor, so as to detect the accuracy and integrity of the dimensions of the components.
7. Inspection of the filling level on the production line: The laser sensor is integrated into the manufacturing of the filling product. When the filling product passes through the sensor, it can detect whether it is filled or not.