Imaging using multiple different narrow bands of light having respective different emission peaks

Patent metadata

Field	Value
Publication number	US-9989763-B2
Application number	US-201514959832-A
Country	US
Kind code	B2
Filing date	Dec 4, 2015
Priority date	Dec 4, 2015
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A near eye or heads up display system includes at least one light source, an imaging device, and an optical structure. The at least one light source can be, e.g., a red light source that produces light within a red wavelength range that has at least two different narrow bands of light having respective different emission peaks. The imaging device produces an image using light produced by the light source(s). The optical structure is configured to transfer light corresponding to the image from an input-pupil to an output-pupil where the image is viewable. By producing at least two different narrow bands of light having respective different emission peaks within a color (e.g., red) wavelength range, and taking advantage of chromatic dispersion, a more uniform intensity distribution is provided in the viewable image compared to if only one narrow band of light within the color wavelength range were produced.

First claim

What is claimed is:

1. A near eye or heads up display system, comprising:
a light source assembly including red, green and blue light sources that are configured to respectively produce red light within a corresponding red wavelength range, green light within a corresponding green wavelength range and blue light within a corresponding blue wavelength range, wherein at least one of the red, green or blue light sources is configured to produce at least two different narrow bands of light that have respective different emission peaks that are within the corresponding wavelength range for the light produced by the light source;
an imaging device configured to produce an image using the red, green and blue light produced by the light source assembly; and
an optical structure including one or more diffractive optical elements and configured to transfer light corresponding to the image, which includes the at least two different narrow bands of light that have respective different emission peaks that are within the corresponding wavelength range, from a common input-pupil to a common output-pupil.

2. The system of claim 1 , wherein the optical structure is also configured to perform pupil expansion.

3. The system of claim 1 , wherein:
for each said light source that is configured to produce at least two different narrow bands of light that have respective different emission peaks that are within the wavelength range for the light source, the at least two different narrow bands of light provide a more uniform intensity distribution in the image viewable at the output-pupil compared to if only one narrow band of light within the wavelength range for the light source were produced.

4. The system of claim 1 , wherein at least one said light source, that is configured to produce at least two different narrow bands of light that have respective different emission peaks that are within the wavelength range for the light source, comprises:
at least two light emitter elements each of which produces a separate one of the different narrow bands of light that have different respective emission peaks that are within the wavelength range for the light source.

5. The system of claim 4 , wherein the at least two light emitter elements comprise:
at least two stripes of a multi-stripe laser diode included in a common die;
at least two stripes of a multi-stripe super luminescent light emitting diode included in a common die;
at least two laser diodes included in at least two separate semiconductor dies that may or may not be included in a same semiconductor package;
at least two super luminescent light emitting diodes included in at least two separate semiconductor dies that may or may not be included in a same semiconductor package; or
at least two quantum dot light emitting diodes.

6. The system of claim 1 , wherein for each said light source that is configured to produce at least two different narrow bands of light that have respective different emission peaks that are within the wavelength range of the light source, a maximum difference in wavelengths between two of the different emission peaks is 50 nm.

7. The system of claim 1 , wherein:
the red wavelength range is from 600 nm to 650 nm;
the green wavelength range is from 500 nm to 550 nm; and
the blue wavelength range is from 430 nm to 480 nm.

8. The system of claim 1 , wherein a full width half maximum (FWHM) of each of the narrow bands of light is less than 10 nm.

9. The system of claim 1 , further comprising:
beam combiner optics configured to combine one or more beams of light produced by one or more of the red, green and blue light sources, or light emitter elements thereof, prior to the beams being provided the imaging device.

10. The system of claim 1 , wherein at least one of the red, green or blue light sources is configured to produce at least three different narrow bands of light that have respective different emission peaks that are within the corresponding wavelength range for the light source.

11. The system of claim 1 , wherein the optical structure comprises an optical waveguide, the optical waveguide including:
an input-coupler configured to couple light corresponding to the image into the optical waveguide; and
an output-coupler configured to couple the light corresponding to the image, which travels in the optical waveguide from the input-coupler to the output-coupler, out of the waveguide so that the light is output and imaged from the output-pupil; and
wherein the input-coupler comprises a said diffractive optical element; and
wherein output-coupler is configured to perform one of horizontal or vertical pupil expansion.

12. The system of claim 11 , wherein:
the waveguide further comprises an intermediate component;
the input-coupler is configured to direct light coupled into the waveguide toward the intermediate-component; and
the intermediate-component is configured to perform the other one of horizontal or vertical pupil expansion and to direct the light
corresponding to the image towards the output-coupler;
wherein at least one of the intermediate-component or the output coupler comprises a said diffractive optical element.

13. A method, comprising:
producing one or more of red, green or blue light, which are respectively, within a corresponding red wavelength range, a corresponding green wavelength range, and a corresponding blue wavelength range,
wherein at least one of the one or more of red, green or blue light is produced to include at least two different narrow bands of light that have respective different emission peaks that are within the corresponding wavelength range of the light;
producing an image using the one or more of red, green or blue light;
utilizing an optical structure to transfer light corresponding to the image from an input-pupil to an output-pupil; and
taking advantage of chromatic dispersion, which occurs due to the at least one of the red, green or blue light including at least two different narrow bands of light that have respective different emission peaks that are within the corresponding wavelength range of the light, to provide a more uniform intensity distribution in the image viewable at the output-pupil, compared to if only one narrow band of light within the corresponding wavelength range were produced.

14. The method of claim 13 , wherein the utilizing the optical structure also includes utilizing the optical structure to perform pupil expansion.

15. The method of claim 13 , wherein:
the red wavelength range is from 600 nm to 650 nm;
the green wavelength range is from 500 nm to 550 nm;
the blue wavelength range is from 430 nm to 480 nn;
a full width half maximum (FWHM) of each of said narrow band of light is less than 10 nm, and
a maximum difference in wavelengths between two of the different emission peaks, within a same corresponding wavelength range of the light, is 50 nm.

16. The method of claim 13 , wherein each one of the red, green or blue light, which is produced to include at least two different narrow bands of light that have respective different emission peaks that are within the corresponding wavelength range of the light, is produced using at least two light emitter elements each of which produces a separate one of the different narrow bands of light that have different respective emission peaks that are within the wavelength range for the light source.

17. The method of claim 16 , wherein the at least two light emitter elements comprise:
at least two stripes of a multi-stripe laser diode included in a common die;
at least tw

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Woltman Scott
• Glik Eliezer

Classifications

• G02B27/0172 Primary

  characterised by optical features · CPC title

• G02B5/18

  Diffraction gratings {(holographic optical elements G02B5/32, G03H; integrally combined with optical fibres G02B6/02057; for coupling light guides G02B6/34; integrally combined with optical integrated light guides G02B6/12; grating systems G02B27/44)} · CPC title

• G02B27/0081

  with means for altering, e.g. enlarging, the entrance or exit pupil · CPC title

• G02B5/1828

  having means for producing variable diffraction (controlling the direction of light by means of one or more diffracting elements G02B26/0808; acousto-optical elements G02F1/11, G02F1/33; electro- or magneto-optical diffraction G02F1/292, G02F1/2955) · CPC title

• G02B2027/0118

  comprising devices for improving the contrast of the display / brillance control visibility · CPC title