×

Reducing speckle in projected images

  • US 9,753,298 B2
  • Filed: 04/08/2014
  • Issued: 09/05/2017
  • Est. Priority Date: 04/08/2014
  • Status: Active Grant
First Claim
Patent Images

1. An image projector comprising:

  • at least one light source for generating display light;

    a despeckle module including;

    a diffuser;

    a first microlens array disposed between the at least one light source and the diffuser, wherein the diffuser is positioned next to the first microlens array to receive the display light from the at least one light source through the first microlens array;

    an in-plane vibrator coupled to vibrate the diffuser along a vibration plane; and

    a vibrator driver coupled to drive the in-plane vibrator, wherein the vibrator driver is configured to drive the in-plane vibrator at different vibration amplitudes for averaging the intensity of speckle in the display light;

    a collimation lens positioned between the at least one light source and the first microlens array;

    a display panel positioned to receive the display light from the despeckle module, wherein the display panel is configured to generate a projectable image using the display light; and

    a second microlens array positioned between the display panel and the diffuser, wherein the second microlens array is positioned next to the diffuser, wherein illumination microlenses in the second microlens array have negative optical power, and wherein the display light encounters the second microlens array after the diffuser.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×