US Patent 11582433 Head up display speckle contrast determination systems and methods

A system for measuring speckle contrast includes: a head up display (HUD) system configured to output a predetermined image and having a first pixels per degree (PPD); an imaging colorimeter: having a field of view; positioned such that the predetermined image is in the field of view; having a second PPD that is at least 2.2 times greater than the first PPD of the HUD system; and configured to capture an image including the predetermined image; and a speckle contrast module configured to determine a speckle contrast of the HUD system based on the image.