The ultra-large field of view bi-telecentric lens has good uniformity in the center of the field of view and around it and has extremely low distortion imaging, which is very suitable for high-precision workpiece appearance inspection and size measurement.
Detection object:
Smartphone cover measurement
Testing requirements:
- Size measurement
- Matching 29MP (full frame 44mm) large area scan camera
- Large field of view FOV 240mm
- High precision
Difficulties in Inspection:
- The field of view is large, and the center and edge of the field of view need to maintain a very consistent resolution
- At the same time for measurement, the distortion needs to be extremely low
- Larger depth of field
Solution
DTCM35FH-240H-AL (DTCM series double telecentric lens) + DTCL-240-1W-G (telecentric parallel backlight)
Test results
- The resolution of the center and edge of the field of view is the same, and the distortion is extremely low (0.004%);
- With parallel backlights, compared with traditional flat-panel backlights, the edges are sharper and the gray transition pixels are fewer. At the same time, the brightness of the center and the periphery of the field of view remains uniform, which maximizes the high resolution characteristics of the lens and greatly improves Accuracy of measurement;
- The effective aperture number is F10.3, while the resolution is guaranteed, the depth of field also meets the project requirements;
