Stereoscopic projection and eye-box steering system for head-up display
A head-up display (HUD) system includes a light transmitter configured to transmit a plurality of light beams corresponding to a stereoscopic image; a multi-lens array comprising a plurality of lenslets arranged in a diffuser plane, where each lenslet has a first portion corresponding to a first area of an eye-box associated with a first eye and a second portion corresponding to a second area of the eye-box associated with a second eye; a two-dimensional (2D) scanner configured to direct each of the plurality of light beams at either the first portion or the second portion of a respective lenslet; and a HUD reflector configured to direct each light beam originating from the first portion of a respective lenslet toward the first area of the eye-box, and direct each light beam originating from the second portion of a respective lenslet toward the second area of the eye-box.
1 . A head-up display (HUD) system, comprising:
a light transmitter configured to transmit a first plurality of light beams corresponding to a first stereo image and a second plurality of light beams corresponding to a second stereo image;
a multi-lens array comprising a plurality of lenslets arranged in a diffuser plane, wherein each lenslet of the plurality of lenslets has a first portion corresponding to a projection of the first stereo image and configured to project light toward a first area of an eye-box corresponding to a first eye, and wherein each lenslet of the plurality of lenslets has a second portion corresponding to a projection of the second stereo image and configured to project light toward a second area of the eye-box;
a two-dimensional (2D) scanner arranged between the light transmitter and the multi-lens array, wherein the 2D scanner is configured to receive the first plurality of light beams from the light transmitter and direct each of the first plurality of light beams at the first portion of a respective lenslet of the plurality of lenslets, and wherein the 2D scanner is configured to receive the second plurality of light beams from the light transmitter and direct each of the second plurality of light beams at the second portion of the respective lenslet; and
a HUD reflector configured to receive the first plurality of light beams from the multi-lens array and direct the first plurality of light beams toward the first area of the eye-box, and receive the second plurality of light beams from the multi-lens array and direct the second plurality of light beams toward the second area of the eye-box.
2 . The HUD system of claim 1 , wherein the first area of the eye-box is configured to correspond to a first eye, and
wherein the second area of the eye-box is configured to correspond to a second eye.
3 . The HUD system of claim 1 , wherein the first plurality of light beams and the second plurality of light beams are collimated beams of pixel light, and
wherein each lenslet of the plurality of lenslets is configured to produce a first divergent light beam from a respective first light beam of the first plurality of light beams, and produce a second divergent light beam from a respective second light beam of the second plurality of light beams.
4 . The HUD system of claim 3 , wherein each first divergent light beam and each second divergent light beam has an angle of divergence, and
wherein a size of the first area of the eye-box and a size of the second area of the eye-box are proportional to the angle of divergence.
5 . The HUD system of claim 4 , wherein the size of the first area of the eye-box and the size of the second area of the eye-box are proportional to or substantially equal to a product of the angle of divergence and a focal length of the HUD reflector.
6 . The HUD system of claim 1 , wherein the HUD reflector is configured to receive the first plurality of light beams from the multi-lens array as a first plurality of divergent light beams, and receive the second plurality of light beams from the multi-lens array as a second plurality of divergent light beams.
7 . The HUD system of claim 6 , further comprising:
a windshield comprising a windshield reflector configured to receive the first plurality of divergent light beams from the HUD reflector and project the first stereo image into the first area of the eye-box, and receive the second plurality of divergent light beams from the HUD reflector and project the second stereo image into the second area of the eye-box.
8 . The HUD system of claim 1 , wherein the HUD system is configured to combine the first stereo image and the second stereo image in the eye-box to produce a stereoscopic image.
9 . The HUD system of claim 1 , wherein each of the first plurality of light beams has a first beam width that is equal to or less than a size of the first portion, and
wherein each of the second plurality of light beams has a second beam width that is equal to or less than a size of the second portion.
10 . The HUD system of claim 9 , wherein the first portion of each lenslet is a first half of the lenslet and the second portion of each lenslet is a second half of the lenslet.
11 . The HUD system of claim 9 , wherein the 2D scanner is configured to direct each of the first plurality of light beams exclusively at the first portion of the respective lenslet, and wherein the 2D scanner is configured to direct each of the second plurality of light beams exclusively at the second portion of the respective lenslet.
12 . The HUD system of claim 1 , wherein the 2D scanner is configured to steer the first plurality of light beams and the second plurality of light beams in a first dimension of the respective lenslet to steer a location of the eye-box.
13 . The HUD system of claim 12 , wherein the 2D scanner is configured to steer the first plurality of light beams and the second plurality of light beams in a second dimension of the respective lenslet to steer the first plurality of light beams at the first portion of the respective lenslet and to steer the second plurality of light beams at the second portion of the respective lenslet.
14 . The HUD system of claim 13 , wherein the 2D scanner is configured to steer the first plurality of light beams and the second plurality of light beams according to a Lissajous scanning pattern.
15 . The HUD system of claim 1 , wherein the 2D scanner is configured to steer the first plurality of light beams in a lateral dimension of the respective lenslet to steer a location of the first area of the eye-box, and
wherein the 2D scanner is configured to steer the second plurality of light beams in the lateral dimension of the respective lenslet to steer a location of the second area of the eye-box.
16 . The HUD system of claim 15 , wherein each of the first plurality of light beams has a first beam width that is equal to or less than 30% of a size of the first portion, and
wherein each of the second plurality of light beams has a second beam width that is equal to or less than 30% of a size of the second portion.
17 . The HUD system of claim 1 , further comprising:
an eye-tracking monitor configured to track a viewing direction of a user,
wherein the 2D scanner is configured to steer the first plurality of light beams and the second plurality of light beams in a lateral dimension of the respective lenslet to steer a location of the eye-box based on the viewing direction of the user.
18 . The HUD system of claim 1 , further comprising:
an eye-tracking monitor configured to track a viewing direction of a user,
wherein the 2D scanner is configured to steer the first plurality of light beams in a lateral dimension of the respective lenslet to steer a location of the first area of the eye-box based on the viewing direction of the user, and
wherein the 2D scanner is configured to steer the second plurality of light beams in the lateral dimension of the respective lenslet to steer a location of the second area of the eye-box based on the viewing direction of the user.