In machine vision systems, lenses are equivalent to human eyes. Their main function is to focus the optical image of the target on the photosensitive array of the image sensor (camera). All image information processed by the vision system is obtained through the lens, and the quality of the lens directly affects the overall performance of the vision system. The following is a detailed explanation of the relevant professional terms of machine vision industrial lenses.
1. Distortion
It can be divided into pincushion distortion and barrel distortion.
2. TV distortion:
The value calculated as the percentage of the actual side length of the distorted shape to the ideal shape.
3. Optical magnification
4. Monitoring and Amplification
Calculation method:
Example: VS-MS1+10x lens 1/2” CCD camera, imaging on 14” monitor
A 0.1mm object is imaged as 44.45mm on the monitor.
※The above simple calculation may vary depending on the scanning status of the TV monitor.
5. Resolution
Indicates the interval between two visible points 0.61x Used wavelength (λ) / NA = resolution (μ)
The above calculation method can theoretically calculate the resolution, but does not include distortion.
※The wavelength used is 550nm
6. Resolution
The number of black and white lines that can be seen in 1mm. Unit: (lp)/mm.
7. MTF (Modulation Transfer Function)
The spatial frequency and contrast used to reproduce the changes in light and dark on the surface of an object when imaging.
8. Working Distance
The distance from the lens barrel to the object
9. O/I (Object to Imager)
The distance between the object and the image is the length from the object to the image.
10. Image Circle
Image size φ, you need to enter the camera sensor size.
11. Camera Mount
C-mount: 1″ diameter x 32 TPI: FB: 17.526mm
CS-mount: 1″ diameter x 32 TPI: FB: 12.526mm
F-mount: FB:46.5mm
M72-Mount: FB Varies between manufacturers
12. Field of View (FOV)
The field of view refers to the range of objects that can be seen by the camera.
The vertical length of the camera's effective area (V) / optical magnification (M) = field of view (V)
Horizontal length of the camera's effective area (H) / optical magnification (M) = field of view (H)
*The field of view shown in the technical data is a value calculated from the general values of the light source and effective area.
The vertical length of the camera's effective area (V) or (H) = the size of one pixel of the camera × the number of effective pixels (V) or (H) is calculated.