Components - Camera

[LigasN]

Camera

It is needed to decide which camera will be used in the scanner. It will be an embedded one. For the experimental stand, it can be a full embedded module equipped with a data interface like SPI or I2C. The resolution needs to be not too small and it doesn't need to be too big. Zoom can be very small as the stand will be not higher than 50 cm and to be honest, in my opinion, it will be not higher than 30 cm as the test area is 20cm x 20cm.

[LigasN]

First of all, I need to choose the resolution of theoretical test images to prove algorithm correctness. I would like to check the market to have the possible resolution of a camera which is available in popular electronic shops.

[LigasN]

So. I did some digging and I have found that my STM NUCLEO-F446RE has a DCMI interface which can make my life incredibly easier. Info is taken from STM32F446RE documentation.

It means for choosing the right camera device, that I don't need to worry about the DCMI interface on the camera module side. I need to buy only a camera device because all synchronizing stuff will be done on my STM32.

I've chosen for now the camera on the link.

[LigasN]

The camera is bought.

[LigasN]

Most important parameters:

• array size: UXGA 1600 x 1200,
• lens size: 1/4",
• chief ray angle: 25° non-linear,
• pixel size: 2.2 um x 2.2 um,
• image area 3590 um x 2684 um,
• sensitivity: 0,6 V/(lux*s).

[LigasN]

These camera properties are applied to the stand_model.blend.

[LigasN]

The most important problem during applying these parameters was the conversion of the chief ray angle into Camera>Lens>Field of View which I solved by FoV ≈ 2* CRA ≈ 50 degrees equation accordingly to knowledge which I've got on the internet research.

The next parameters were:

• Camera>Camera>Size = pixel size * 1200 (lower resolution side),
• Camera>Viewport Display>Size = 20cm (max edge length of the captured object),
• Scene>Format>Resolution = 1200px x 1200px,
• Scene>Render Engine = Eevee.

[LigasN]

[LigasN]

Camera is changed to Raspberry Pi v2 module. I need to investigate Camera>Lens>Field of View parameter and provide its parameters here.