Microelectromechanical system over-scanning for pupil distance compensation

Abstract

Disclosed herein are devices and methods to provide a display including a projection system and a lens including a holographic optical element to receive light and reflect the light to an exit pupil. The projection system is adapted to move the image projected onto the lens based on a location of the HOE within the lens.

1 . An apparatus, comprising:
 a microelectromechanical system (MEMS) mirror arranged to oscillate about an oscillation axes, the MEMS mirror to receive light from a light source and reflect the light to a lens including a holographic optical element in a first location, the holographic optical element having a surface area smaller than a surface area of the lens, the light corresponding to a plurality of pixels of an image;   a controller to send a control signal to the light source, the control signal to include an indication of a first start time of a first one of the plurality of pixels in relation to a period of oscillation of the MEMS mirror to shift the image to a location on the lens corresponding to first location.   
     
     
         2 . The apparatus of  claim 1 , the MEMS mirror arranged to oscillate from a first point on the oscillation axes to a second point on the oscillation axes and from the second point on the oscillation axes to the first point on the oscillation axes, the first start time comprising a delay from the first point. 
     
     
         3 . The apparatus of  claim 2 , the control signal comprising an indication of a second start time of a second one of the plurality of pixels in relation to the period of oscillation of the MEMS mirror. 
     
     
         4 . The apparatus of  claim 3 , the second start time comprising a delay from the second point. 
     
     
         5 . The apparatus of  claim 4 , wherein the delay from the first point is the same as the delay from the second point, greater than the delay from the second point, or less than the delay from the second point. 
     
     
         6 . The apparatus of  claim 1 , the control signal comprising an indication of a spacing between each of the plurality of pixels. 
     
     
         7 . The apparatus of  claim 6 , wherein the spacing between at least two of the plurality of pixels is different. 
     
     
         8 . The apparatus of  claim 6 , the indication of the spacing between each of the plurality of pixels comprising a first direction spacing and a second direction spacing, the first direction spacing corresponding to a first direction of oscillation of the MEMS mirror and the second direction spacing corresponding to a second direction of oscillation of the MEMS mirror. 
     
     
         9 . The apparatus of  claim 8 , wherein the first direction spacing between a first and a second one of the plurality of pixels is different than the second direction spacing between the first and the second one of the plurality of pixels. 
     
     
         10 . A method comprising:
 oscillating a microelectromechanical system (MEMS) mirror about an oscillation axes;   directing light from a light source at the MEMS mirror, the MEMS mirror to reflect the light to a lens including a holographic optical element in a first location, the holographic optical element having a surface area smaller than a surface area of the lens, the light corresponding to a plurality of pixels of an image; and   sending a control signal to the light source, the control signal to include an indication of a first start time of a first one of the plurality of pixels in relation to a period of oscillation of the MEMS mirror to shift the image to a location on the lens corresponding to first location.   
     
     
         11 . The method of  claim 10 , comprising oscillating the MEMS mirror from a first point on the oscillation axes to a second point on the oscillation axes and from the second point on the oscillation axes to the first point on the oscillation axes, the first start time comprising a delay from the first point. 
     
     
         12 . The method of  claim 11 , the control signal comprising an indication of a second start time of a second one of the plurality of pixels in relation to the period of oscillation of the MEMS mirror. 
     
     
         13 . The method of  claim 12 , the second start time comprising a delay from the second point. 
     
     
         14 . The method of  claim 13 , wherein the delay from the first point is the same as the delay from the second point, greater than the delay from the second point, or less than the delay from the second point. 
     
     
         15 . The method of  claim 10 , the control signal comprising an indication of a spacing between each of the plurality of pixels, wherein the spacing between each of the plurality of pixels is the same. 
     
     
         16 . At least one non-transitory machine-readable storage medium comprising instructions that when executed by a processor, cause the processor to:
 direct light from a light source at a microelectromechanical system (MEMS) mirror, the light corresponding to a plurality of pixels of an image, the MEMS mirror to oscillate about an oscillation axes and to reflect the light to a lens including a holographic optical element in a first location, the holographic optical element having a surface area smaller than a surface area of the lens; and   send a control signal to the light source, the control signal to include an indication of a first start time of a first one of the plurality of pixels in relation to a period of oscillation of the MEMS mirror to shift the image to a location on the lens corresponding to first location.   
     
     
         17 . The at least one non-transitory machine-readable storage medium of  claim 16 , comprising instructions that further cause the processor to oscillate the MEMS mirror about the oscillation axes. 
     
     
         18 . The at least one non-transitory machine-readable storage medium of  claim 17 , comprising instructions that further cause the processor to oscillate the MEMS mirror from a first point on the oscillation axes to a second point on the oscillation axes and from the second point on the oscillation axes to the first point on the oscillation axes, the first start time comprising a delay from the first point. 
     
     
         19 . The at least one non-transitory machine-readable storage medium of  claim 18 , the control signal comprising an indication of a second start time of a second one of the plurality of pixels in relation to the period of oscillation of the MEMS mirror, the second start time comprising a delay from the second point, wherein the delay from the first point is the same as the delay from the second point, wherein the delay from the first point is greater than the delay from the second point, or wherein the delay from the first point is less than the delay from the second point. 
     
     
         20 . The at least one non-transitory machine-readable storage medium of  claim 17 , the control signal comprising an indication of a spacing between each of the plurality of pixels, wherein the spacing between each of the plurality of pixels is the same or wherein the spacing between at least two of the plurality of pixels is different. 
     
     
         21 . The at least one non-transitory machine-readable storage medium of  claim 20 , the indication of the spacing between each of the plurality of pixels comprising a first direction spacing and a second direction spacing, the first direction spacing corresponding to a first direction of oscillation of the MEMS mirror and the second direction spacing corresponding to a second direction of oscillation of the MEMS mirror. 
     
     
         22 . The at least one non-transitory machine-readable storage medium of  claim 21 , wherein the first direction spacing between a first and a second one of the plurality of pixels is different than the second direction spacing between the first and the second one of the plurality of pixels. 
     
     
         23 . A system for projecting an image, the system comprising:
 a frame to removably receive a first one of a plurality of projection surfaces, each of the plurality of projection surfaces comprising a holographic optical element (HOE), the HOE to have a surface area smaller than a surface area of the plurality of projection surfaces, the first one of the plurality of projection surfaces to comprise a first HOE in a first location; and   a projection system coupled to the frame, the projection system comprising:
 a light source to emit light corresponding to a plurality of pixels of an image; 
 a microelectromechanical system (MEMS) mirror arranged to oscillate about an oscillation axes, to receive the emitted light and to reflect the light to the first one of the plurality of projection surfaces; and 
 a controller to send a control signal to the light source, the control signal to include an indication of a first start time of a first one of the plurality of pixels in relation to a period of oscillation of the MEMS mirror to shift the image to a location on the first one of the plurality of projection surfaces corresponding to first location. 
   
     
     
         24 . The system of  claim 23 , wherein the first start time depends upon the location of the HOE of the first one of the projection surfaces. 
     
     
         25 . The system of  claim 23 , the MEMS mirror arranged to oscillate from a first point on the oscillation axes to a second point on the oscillation axes and from the second point on the oscillation axes to the first point on the oscillation axes, the first start time comprising a delay from the first point.