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The $200 CV camera is a global shutter camera with a 40° FOV an advertized 40° diagonal field of view (FOV) 8mm rectilinear lens (smallest FOV available).

Product webpage: https://hupuu.com/camera/1080p-2mp-global-shutter-color-usb-camera-module-yuy2-usb2.0-100fps-mjpeg?sku=UCB543-GS-L8N

• UCB543-GS-L8N

Specifications:

• Resolution: WUXGA (1920px x 1200px)

• Maximum frame rate: 100FPS (5FPS typical)

• Exposure: Automatic or manual

  • Default is automatic and is very aggressive in reducing exposure (images appear dark)

• Lens: 8mm rectilinear (40° FOV)

• Connector: USB-A, USB 2.0 plug and play

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Test the camera with Python (e.g. https://docs.opencv.org/4.7.0/dd/d43/tutorial_py_video_display.html ), an application on the computer, or a webcam testing website.

The focus distance can be changed by rotating the lens along the threads of the lens holder.

Hardware

Lens FOV

For 8mm lens ordered with sensor:

• Horizontal FOV: ~37.178° = ~0.64889rad

• Vertical FOV: ~23.742° = ~0.41438rad

Exact measurements below.

Note: There is some distortion in the lens (i.e. straight lines in the world appear slightly curved outwards).

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Measurement

Print and place square grid paper on flat surface.

• A grid on an electronic screen works as well.

Measure ratio of square side length to SI unit.

• 23squares : 13cm

Plug the camera into computer and display the video.

Point the camera perpendicularly to the grid and ensure that grid is aligned with the edges of the video frame.

Change the distance of the camera from the grid so that there is a whole number of squares from left edge to right edge of video frame. Record the count.

• 18squares width

Without moving the camera, measure the perpendicular distance from the grid to the closest end of the camera lens.

• 15cm to end of lens

Estimate the focal point of the lens.

• 2.5mm lens end length, focal point estimated halfway

Calculate the horizontal field of view:

1. Convert the horizontal distance to SI units:

   1. Horizontal distance in SI = Square count * (Square side length in SI units / Square side length in squares)

2. Convert perpendicular distance to the same units as the horizontal distance

3. Triangle ratio:

   1. Opposite over adjacent = Horizontal distance / 2 / Perpendicular distance

4. Get the angle:

   1. Angle = arctan(Opposite over adjacent)

5. Final answer:

   1. Horizontal field of view = Angle * 2

Calculate the vertical field of view:

1. Follow steps 1-3 of horizontal field of view

2. Multiply by ratio correction:

   1. Correction = Vertical resolution / Horizontal resolution

3. Follow steps 4-5 of horizontal field of view

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Combined:

~37.178° = ~0.64889rad = arctan(18 * (13 / 23) / 2 / 15.125) * 2
~23.742° = ~0.41438rad = arctan(18 * (13 / 23) / 2 / 15.125 * (10 / 16)) * 2

Electrical

Input voltage: 5VDC

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No operating constraints. Does not require active cooling.

Other

The lens holder is fixed focus adjustable S-mount (M12).

Reference Images

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