Blurry Images

Why does it happen?

There are mainly two reasons for an image to be blurred.

  • The camera is out of focus

  • Image areas are oversaturated

What causes this effect?

The blurry effect refers to a phenomenon wherein light ‘bleeds’ from areas with excess light to areas of lower light. What actually happens is that light (photons) that is supposed to be centered in one pixel is scattered to neighboring pixels and vice versa. This reduces the strength of the signal at a given pixel, while noise is increased due to incoming light from neighboring pixels. This results in a lower Signal-to-Noise ratio (SNR). SNR describes how well Zivid can read back the projected signal for a given pixel.

Pixel bleeding into neighboring pixels

How to remove it?

  • Out of focus

    Ensure that the scene is in focus by using the camera within its optimal range. Calculate FOV and Imaging Distance can be used to check for this. Also, make sure that the depth of field is large enough as this depends on aperture settings for the acquisition(s). How aperture values change the depth of field is explained here.

  • Oversaturated areas

    Check the 2D image to ensure that you do not have areas that are oversaturated. Reduce the exposure time or lower the active aperture setting to counter this. Think of pixels as bins; if they are full, they run over to neighboring bins (pixels).