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I have always wondered if it's possible to make a homemade primitive photo sensor for capturing photos in an acceptable range and in low resolution using environmental light? I know that it's possible to use the mechanism of an optical mouse for scanning documents with very low resolutions, but it fails at longer distances than a few millimeters.

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  • \$\begingroup\$ You could build a matrix of photodiodes, and read the voltages across all of the diodes sequentially using a microcontroller. The voltage is proportional to the light intensity. Or use small solar cells the same way. \$\endgroup\$ – JRE Jun 15 '17 at 20:02
  • \$\begingroup\$ Do you mean a light-field camera? \$\endgroup\$ – Janka Jun 15 '17 at 20:07
  • \$\begingroup\$ Exactly how low-level of an answer are you looking for? In other words, are you building a home-made imaging device on top of a commercial array sensor or are you trying to build that array sensor itself at home? \$\endgroup\$ – Vladislav Martin Jun 15 '17 at 20:41
  • \$\begingroup\$ It only fails at longer range because the optics are set up for short range. It might well be possible to provide supplementary optics which would allow better performance, but you'd also have to hack the sensor - and modern mouse sensors are so tightly integrated that trying to get access to the photosensor output (prior to the processing section) would be a nightmare. \$\endgroup\$ – WhatRoughBeast Jun 15 '17 at 20:46
  • \$\begingroup\$ @JRE Yes, but I guess that would need the object to have tremendous amounts of light on it. \$\endgroup\$ – Adrian Machin Jun 15 '17 at 20:48
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One option would be

  • Mount a small photo-sensor on an X-Y carriage positioned on the focal plane of your "camera".
  • The shutter would be left open permanently and the sensor stepped across each line in turn taking as many samples as you want to construct your image.
  • An analog grey-scale reading could be taken at each point, shifted into memory and a grey-scale bitmap created from the results.

Here's a variation on the idea: enter image description here

Figure 1: A single-pixel camera on a pan and tilt mechanism. Source: Arduining.com.

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  • \$\begingroup\$ Thanks, but that project would only read from a bright display. I'm looking for something that could capture real images like a camera or webcam. \$\endgroup\$ – Adrian Machin Jun 15 '17 at 20:51
  • \$\begingroup\$ Well change the sensor then to one that's sensitive enough for your requirements. \$\endgroup\$ – Transistor Jun 15 '17 at 20:53

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