Diffraction grating design
AssigneeApple Inc.
InventorsYongming Tu, Alfredo Bismuto
Life of this patent
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Abstract
Configurations for a diffraction grating design and methods thereof are disclosed. The diffraction grating system can include an input waveguide located at a first location on or near a Rowland circle and multiple output waveguides located at a second and third location on or near the Rowland circle. The input waveguide may be located between the output waveguides and this configuration of input and output waveguides can reduce the footprint size of the device. In some examples, the optical component can function as a de-multiplexer. Additionally, the optical component may separate the input wavelength band into two output wavelength bands which are separated from one another by approximately 0.1 μm.
Claims18
An optical device, comprising:
- a planar waveguide defining an input light path;
- an input waveguide configured to emit light along the input light path;
- a set of grating facets configured to:
- receive the emitted light from the input waveguide;
- and
- reflect the emitted light as a first reflected light and a second reflected light;
- a first output waveguide defining a first reflected light path and configured to receive the first reflected light along the first reflected light path;
- and
- a second output waveguide defining a second reflected light path and configured to receive the second reflected light along the second reflected light path, wherein:
- the first reflected light is a first wavelength of light reflected at a first angle and to the first output waveguide;
- the second reflected light is a second wavelength of light reflected at a second angle and to the second output waveguide;
- and
- a power distribution of the first wavelength range of light received by the first output waveguide and the second wavelength range of light received by the second output waveguide is based at least in part on a blaze angle of the set of grating facets.
An optical device, comprising:
- a first light emitting element configured to emit a first input light along a first input light path and positioned at a first location on a Rowland circle;
- a second light emitting element configured to emit second input light along a second input light path;
- a light receiving element configured to receive reflected light along a reflected light path and positioned at a second location on the Rowland circle and between the first light emitting element and the second light emitting element;
- and
- a diffraction grating configured to:
- receive light along the input light path of the light emitting element;
- and
- reflect light along the reflected light path to the light receiving element.
A method for splitting light, comprising:
- emitting light in a broadband wavelength range from a first position on a Rowland circle;
- reflecting the light from an Echelle grating in the broadband wavelength range;
- receiving a first reflected light in a first wavelength band of the broadband wavelength range and at a second position on the Rowland circle;
- and
- receiving a second reflected light in a second wavelength band of the broadband wavelength range and at a third position on the Rowland circle, the second wavelength band separated from the first wavelength band by at least 0.1 μm, wherein the first position on the Rowland circle is between the second position and the third position.
Dependencies are inferred from the claim text.