OPTICAL SYSTEM AND METHOD FOR TRANSMITTING A SOURCE IMAGE

• US 20180299678A1
• Filed: 06/14/2018
• Published: 10/18/2018
• Est. Priority Date: 12/17/2015
• Status: Active Grant

• Current Assignee: Carl Zeiss AG (Carl-Zeiss-Stiftung)
• Original Assignee: Carl Zeiss AG (Carl-Zeiss-Stiftung)
• Inventors: Singer, Wolfgang, Kleemann, Bernd, Degen, Artur
• Granted Patent: US 10,191,288 B2
• Time in Patent Office: Days
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0112 comprising device for genereting colour display
• CPC Class Codes: G02B 2027/0116 comprising devices for correcting chromatic aberration
• CPC Class Codes: G02B 2027/0125 Field-of-view increase by wavefront division
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/1819 Plural gratings positioned on the same surface, e.g. array of gratings plural diffractive elements positioned sequentially along the optical path G02B27/4272
• CPC Class Codes: G02B 6/0026 Wavelength selective element, sheet or layer, e.g. filter or grating
• CPC Class Codes: G02B 6/005 provided by one optical element, or plurality thereof, placed on the light output side of the light guide
• CPC Class Codes: G02B 6/0076 Stacked arrangements of multiple light guides of the same or different cross-sectional area

Abstract

An optical system for transmitting a source image is provided. Light having a field angle spectrum emanates from the source image. The optical system includes an optical waveguide arrangement, in which light can propagate by total internal reflection. The optical system also includes a diffractive optical input coupling arrangement for coupling the light emanating from the source image into the optical waveguide arrangement. The optical system further includes a diffractive optical output coupling arrangement for coupling the light that has propagated in the optical waveguide arrangement out from the optical waveguide arrangement. The disclosure also provides related methods.

Claims

1. An optical system configured to transmit a source image from which light having a field angle spectrum emanates, the optical system comprising:

an optical waveguide arrangement in which the light can propagate by total internal reflection;

a diffractive optical input coupling arrangement configured to couple the light emanating from the source image into the optical waveguide arrangement; and

a diffractive optical output coupling arrangement configured to couple the light that has propagated in the optical waveguide arrangement out from the optical waveguide arrangement,

wherein;

the input coupling arrangement comprises;

a first input coupling element configured to couple light from a first subfield of the source image having field angles from a first field angle range of the field angle spectrum into the optical waveguide arrangement;

a second input coupling element configured to couple light from a second subfield of the source image having field angles from a second field angle range;

the second subfield is at least partly different from the first subfield;

the second field angle range is at least partly different from the first field angle range;

the transmitted first subfield and the transmitted at least one second subfield are at least partly superimposed on each other after coupling out from the optical waveguide arrangement; and

at least one subfield selected from the group consisting of the first subfield and the second subfield is at least partly arcuately bounded before coupling into the optical waveguide arrangement.

2. The optical system of claim 1, wherein:

the first subfield has a first field edge;

the second subfield has a second field edge;

the first field edge is directly adjacent to the second field edge; and

one of the following holds;

the first field edge is concavely arcuate and the second field edge is convexly arcuate; and

the first field edge is convexly arcuate and the second field edge is concavely arcuate.

3. The optical system of claim 2, wherein the first and second subfields partially overlap in a region of the first and second field edges.

4. The optical system of claim 2, wherein:

the input coupling arrangement comprises a third input coupling element configured to couple in a third subfield of the source image;

the third subfield is arranged between the first and second subfields;

the third subfield has third field edges of which one is directly adjacent to the first field edge and the other is directly adjacent to the second field edge; and

both third field edges are arcuate.

5. The optical system of claim 1, wherein at least one subfield selected from the group consisting of the first subfield and the second subfield is arcuately bounded at an outer field edge.

6. The optical system of claim 1, wherein:

the input coupling arrangement has a number of N input coupling elements configured to couple light from N different subfields of the source image having field angles from N at least partly different field angle ranges of the field angle spectrum into the optical waveguide arrangement; and

N is an integer greater than 2.

7. The optical system of claim 1, wherein:

the input coupling arrangement comprises two first and two second input coupling elements;

one of the two first and one of the two second input coupling elements are configured to couple light from the first and second subfields, respectively, in a first wavelength range into the optical waveguide arrangement;

the other of the two first and second input coupling elements are configured to couple light from the first and second subfields), respectively, in a second wavelength range into the optical waveguide arrangement; and

the second wavelength range is different from the first wavelength range.

8. The optical system of claim 7, wherein the optical waveguide arrangement comprises:

a first optical waveguide configured to the propagate light in the first wavelength range; and

a separate second optical waveguide configured to propagate light in the second wavelength range.

9. The optical system of claim 1, wherein the optical waveguide arrangement comprises:

a first optical waveguide into which the first input coupling element couples the light from the first subfield; and

a second optical waveguide into which the second input coupling element couples the light from the second subfield.

10. The optical system of claim 9, wherein the first output coupling element is configured to couple light out from the first optical waveguide, and the second output coupling element is configured to couple light out from the second optical wave-guide.

11. The optical system of claim 1, wherein:

the optical waveguide arrangement comprises an optical waveguide into which the first input coupling element couples the light from the first subfield and the input coupling element couples in the light from the second subfield; and

the first and second input coupling elements are arranged in opposite end regions of the optical waveguide.

12. The optical system of claim 11, wherein the first and second output coupling elements are configured to couple light out from the one optical waveguide.

13. The optical system of claim 12, wherein:

the output coupling arrangement comprises a plurality of first output coupling elements and a plurality of second output coupling elements; and

the first and second output coupling elements are arranged alternately along the optical waveguide.

14. The optical system of claim 11, wherein the output coupling arrangement comprises only one output coupling element.

15. The optical system of claim 1, wherein:

the optical waveguide arrangement comprises an optical waveguide into which the first input coupling element couples the light from the first subfield and the second input coupling element couples the light from the subfield;

the optical waveguide comprises two mutually parallel first and second sections and at a first end a third section perpendicular to the first and second sections; and

the first and second input coupling elements are arranged at free second ends of the optical waveguide.

16. The optical system of claim 1, wherein the output coupling arrangement comprises:

a first output coupling element configured to couple light from the first subfield of the source image out from the optical waveguide arrangement; and

a second output coupling element configured to couple light from the second subfield of the source image out from the optical waveguide arrangement.

17. The optical system of claim 1, wherein at least one member selected from the group consisting of the first input coupling element and the second input coupling element comprises a transmissive optical diffraction grating structure.

18. The optical system of claim 1, wherein at least one member selected from the group consisting of the first input coupling element and the second input coupling element comprises a reflective optical diffraction grating structure.

19. The optical system of claim 1, further comprising a device configured to divide the source image into the first and second subfields.

20. A method of transmitting a source image from which light having a field angle spectrum emanates, the method comprising:

dividing the light emanating from the source image into first and second subfields, the light of the first subfield having field angles in a first field angle range of the field angle spectrum, the light of the second subfield having field angles in a second field angle range of the field angle spectrum which is at least partly different from the first field angle range, at least one subfield selected from the group consisting of the first subfield and the second subfield being arcuately bounded;

diffractively coupling in light of the first subfield and, separately from the input coupling of the light of the first subfield, diffractively coupling in the second subfield into an optical waveguide arrangement;

propagating the light of the first and second subfields in the optical waveguide arrangement; and

diffractively coupling out the first and second subfields from the optical waveguide arrangement so that the transmitted first subfield and the transmitted second subfield are at least partly superimposed on one each other after coupling out from the optical waveguide arrangement.