Projector architecture incorporating artifact mitigation
An eyepiece for projecting an image includes a first planar waveguide positioned in a first lateral plane. The first planar waveguide comprises a first diffractive optical element (DOE) disposed at a first lateral position. The eyepiece also includes a second planar waveguide positioned in a second lateral plane adjacent to the first lateral plane. The second planar waveguide comprises a second DOE disposed at a second lateral position different from the first lateral position. The eyepiece further includes a third planar waveguide positioned in a third lateral plane adjacent to the second lateral plane. The third planar waveguide comprises a third DOE disposed at a third lateral position different from the first lateral position and the second lateral position. The eyepiece also includes an optical filter positioned between the second planar waveguide and the third planar waveguide. The optical filter is disposed at the third lateral position.
1. An eyepiece for projecting an image to an eye of a viewer, the eyepiece comprising:
a first planar waveguide positioned in a first lateral plane at a first longitudinal position, wherein the first planar waveguide comprises a first diffractive optical element (DOE) disposed at a first lateral position in the first lateral plane, the first longitudinal position being measured along an axis normal to the first lateral plane;
a second planar waveguide positioned in a second lateral plane adjacent to the first lateral plane and at a second longitudinal position, wherein the second planar waveguide comprises a second DOE disposed at a second lateral position in the second lateral plane, the second lateral position being different from the first lateral position and the second longitudinal position being different from the first longitudinal position;
a third planar waveguide positioned in a third lateral plane adjacent to the second lateral plane and at a third longitudinal position, wherein the third planar waveguide comprises a third DOE disposed at a third lateral position in the third lateral plane, the third lateral position being different from the first lateral position and the second lateral position and the third longitudinal position being different from the first longitudinal position and the second longitudinal position; and
an optical filter positioned between the second planar waveguide and the third planar waveguide, wherein the optical filter is disposed at the third lateral position.
2. The eyepiece of claim 1 wherein the optical filter comprises a long pass filter operable to transmit a first wavelength range and reflect a second wavelength range less than the first wavelength range.
3. The eyepiece of claim 2 wherein the first wavelength range includes 600 nm to 700 nm and the second wavelength range includes 400 nm-500 nm.
4. The eyepiece of claim 2 wherein transmittance at the first wavelength range is approximately 90% or greater.
5. The eyepiece of claim 2 wherein reflectance at the second wavelength range is approximately 10% or less.
6. The eyepiece of claim 1 wherein the optical filter comprises a long pass filter operable to transmit a first wavelength range and absorb a second wavelength range.
7. The eyepiece of claim 1 wherein:
the first planar waveguide has a first surface and a second surface opposite to the first surface, the first planar waveguide having a first region including the first lateral position and a second region, the first region configured to receive image light incident on the first surface thereof, the image light including image light in a first wavelength range; and
the first DOE is disposed in the first region and configured to diffract image light in the first wavelength range into the first planar waveguide to be guided toward the second region of the first planar waveguide, wherein a portion of the image light is transmitted through the first planar waveguide.
8. The eyepiece of claim 1 wherein:
the second planar waveguide has a first surface and a second surface opposite to the first surface, the second planar waveguide having a first region including the second lateral position and a second region, the first region configured to receive image light in a second wavelength range; and
the second DOE is disposed in the first region and is configured to diffract the image light in the second wavelength range into the second planar waveguide to be guided toward the second region of the second planar waveguide.
9. The eyepiece of claim 8 wherein the optical filter is disposed on the first surface or the second surface of the first planar waveguide or the first surface or the second surface of the second planar waveguide.
10. The eyepiece of claim 1 wherein:
the third planar waveguide has a first surface and a second surface opposite to the first surface, the third planar waveguide having a first region including the third lateral position and a second region, the first region configured to receive image light in a third wavelength range; and
the third DOE is disposed in the first region and is configured to diffract the image light in the third wavelength range into the third planar waveguide to be guided toward the second region of the third planar waveguide.
11. The eyepiece of claim 10 wherein the optical filter is disposed on the first surface of the third planar waveguide.
12. The eyepiece of claim 10 wherein the third DOE is disposed on the second surface of the third planar waveguide.