Stereoscopic glasses using dichroic and absorptive layers
View Patent ↗Filter glasses for use with a stereoscopic digital display system that displays stereoscopic images including left-eye images and right-eye images. The left-eye images are formed with light in a plurality of left-eye spectral bands, and the right-eye images are formed with light in a corresponding plurality of spectrally-adjacent right-eye spectral bands. The filter glasses include a left-eye filter and a right-eye filter, each of which includes a dichroic filter stack and one or more absorptive filter layers. Each of the filters transmits 50% or more of the light in the corresponding eye spectra bands, while providing less than 5% crosstalk. A frame is used to position the right-eye filter in front of an observer's right eye and to position the left-eye filter in front of the observer's left eye.
1. Filter glasses for use with a stereoscopic display system that outputs, toward a display surface, stereoscopic images including left-eye images from left-eye emitters and right-eye ages from right-eye emitters, the filter glasses comprising:
a frame with an outer end and an inner end, the outer end being positionable closer to the display surface than the inner end, the inner end being positionable closer to eyes of a filter glasses wearer than the outer end, the frame comprising:
a left-eye filter including a left-eye dichroic filter stack and a left-eye absorptive filter layer positioned at the outer end or closer to the outer end than the left-eye dichroic filter stack, the left-eye dichroic filter stack being positioned closer to the inner end than the left-eye absorptive filter layer and configured to transmit 60% or more of light from the left-eye light emitters and reflect 60% or more of the light from the right-eye light emitters, the left-eye absorptive filter layer being configured to transmit a larger percentage of the light from the left-eye light emitters than the light from the right-eye light emitters; and
a right-eye filter including a right-eye dichroic filter stack and a right-eye absorptive filter layer positioned at the outer end or closer to the outer end than the right-eye dichroic filter stack, the right-eye dichroic filter stack being positioned closer to the inner end than the right-eye absorptive filter layer and configured to transmit 60% or more of the light from the right-eye light emitters and reflect 60% or more of the light from the left-eye light emitters, the right-eye absorptive filter layer being configured to transmit a larger percentage of the light from the right-eye light emitters than the light from the left-eye light emitters,
wherein the right-eye absorptive filter layer and the left-eye absorptive filter layer are configured to absorb unwanted light from the display surface before the unwanted light can be received by the right-eye dichroic filter stack and the left-eye dichroic filter stack to prevent the right-eye dichroic filter stack and the left-eye dichroic filter stack from reflecting the unwanted light toward the display surface.
2. The filter glasses of claim 1 wherein the left-eye filter is configured to reflect 50% or less of the light from the right-eye light emitters that is incident on the left-eye filter from the direction of the display surface, and wherein the right-eye filter is configured to reflect 50% or less of the light from the left-eye light emitters that is incident on the right-eye filter from the display surface.
3. The filter glasses of claim 1 wherein at least some of the left-eye absorptive filter layers are positioned between the left-eye dichroic filter stack and the observer's left-eye, and wherein at least some of the right-eye absorptive filter layers are positioned between the right-eye dichroic filter stack and the observer's right-eye.
4. The filter glasses of claim 3 wherein the left-eye filter is configured to reflect 50% or less of the light from the right-eye light emitters that is incident on a surface of the left-eye filter closest to the observer's left eye, and wherein the right-eye filter is configured to reflect 50% or less of the light from the left-eye light emitters that is incident on a surface of the right-eye filter closest to the observer's right eye.
5. The filter glasses of claim 1 wherein the left-eye dichroic filter stack is on one side of a left-eye substrate and at least some of the left-eye absorptive filter layers are on the other side of the left-eye substrate, and wherein the right-eye dichroic filter stack is on one side of a right-eye substrate and at least some of the right-eye absorptive filter layers are on the other side of the right-eye substrate.
6. The filter glasses of claim 1 wherein the filter layers for the right-eye filter and the left-eye filter further include one or more filter layers forming an anti-reflection coating.
7. The filter glasses of claim 6 wherein the anti-reflection coating is formed as part of the corresponding dichroic filter stack.
8. The filter glasses of claim 1 wherein the left-eye dichroic filter stack and the right-eye dichroic filter stack include layers of vacuum-deposited materials, the vacuum deposited materials including dielectrics, metals, metallic oxides or non-metallic oxides, or combinations thereof.
9. The filter glasses of claim 1 wherein at least one filter layer is deposited as a solution of nanoparticles.
10. The filter glasses of claim 1 wherein the left-eye dichroic filter stack and the right-eye dichroic filter stack are fabricated from extruded materials.
11. The filter glasses of claim 1 wherein one or both of the left-eye absorptive filter layers and the right eye absorptive filter layers include absorbing dyes or pigments.
12. The filter glasses of claim 1 wherein one or both of the left-eye absorptive filter layers and the right eye absorptive filter layers include metamaterials or photonic crystals.
13. The filter glasses of claim 1 wherein the left-eye absorptive filter layers and the right eye absorptive filter layers include nanoparticles.
14. The filter glasses of claim 13 wherein the nanoparticles include virus or protein molecules.
15. The filter glasses of claim 1 wherein the left-eye light emitters and the right-eye light emitters include solid-state lasers or LEDs.
16. The filter glasses of claim 1 wherein the left-eye spectral bands and the right-eye spectral bands have full-width, half-maximum bandwidths of less than 15 nm.