High-resolution single photodiode spectrometer using a narrowband optical filter

1. An optical device, comprising:

a narrowband optical filter to:

receive a beam of light at a selected angle of incidence,

wherein the beam of light is caused to be received by the narrowband optical filter at the selected angle of incidence by a steering element included in the optical device; and

output a filtered beam of light associated with the beam of light,

wherein a wavelength of the filtered beam of light depends on the selected angle of incidence of the beam of light on the narrowband optical filter;

a photodiode to receive at least a portion of the filtered beam of light after the filtered beam of light is outputted by the narrowband optical filter; and

a light pipe to direct the filtered beam of light to a sample.

2. The optical device of claim 1 , wherein the narrowband optical filter is an ultra-narrow bandpass (UNBP) filter.

3. The optical device of claim 1 , wherein the steering element includes a micro-electro-mechanical system (MEMS) mirror.

4. The optical device of claim 1 , wherein the steering element includes a set of curved reflective optical elements.

5. The optical device of claim 1 , wherein the narrowband optical filter is arranged to send the filtered beam of light to the sample such that at least a portion of the beam of light is reflected or transmitted to the photodiode by the sample.

6. The optical device of claim 1 , wherein the narrowband optical filter is arranged to receive the beam of light after reflection or transmission by the sample.

7. The optical device of claim 6 , further comprising a collimating element to send the beam of light to the steering element.

8. The optical device of claim 1 , further comprising an emitter to emit the beam of light.

9. The optical device of claim 1 , wherein the steering element includes an emitter that emits the beam of light,

wherein the emitter is one of a plurality of emitters, each being arranged to emit a respective beam of light at a different angle with respect to the narrowband optical filter.

10. The optical device of claim 1 , wherein the optical device is a spectrometer.

11. A method, comprising:

receiving, by a narrowband optical filter included in an optical device, a beam of light at a selected angle of incidence,

wherein the beam of light is caused to be received by the narrowband optical filter at the selected angle of incidence by a steering element included in the optical device, and

wherein the steering element includes a micro-electro-mechanical system (MEMS) mirror and one or more curved reflective optical elements;

outputting, by the narrowband optical filter, a filtered beam of light associated with the beam of light,

wherein a wavelength of the filtered beam of light is governed by the selected angle of incidence; and

receiving, by a photodiode included in the optical device, a portion of the filtered beam of light after the filter beam of light is outputted by the narrowband optical filter.

12. The method of claim 11 , wherein the photodiode receives the portion of the filtered beam of light after the filter beam of light interacts with a sample.

13. The method of claim 11 , wherein the narrowband optical filter is an ultra-narrow bandpass (UNBP) filter.

14. The method of claim 11 , wherein the one or more curved reflective optical elements include a set of curved reflective optical elements.

15. The method of claim 11 , further comprising an emitter to emit the beam of light.

16. A spectrometer, comprising:

a steering element comprising:

a micro-electro-mechanical system (MEMS) mirror to reflect a beam of light, and

a curved reflective optical element to direct the beam of light such that the beam of light is incident on a narrowband optical filter at a particular angle of incidence;

the narrowband optical filter to filter the beam of light in order to create a filtered beam of light, wherein a wavelength of the filtered beam of light depends on the particular angle of incidence; and

a photodiode to receive at least a portion of the filtered beam of light.

17. The spectrometer of claim 16 , wherein the narrowband optical filter is an ultra-narrow bandpass interference (UNBP) filter.

18. The spectrometer of claim 16 , further comprising an emitter to emit the beam of light.

19. The spectrometer of claim 16 , wherein the curved reflective optical element is a concave elliptical mirror.

20. The spectrometer of claim 16 , wherein the MEMS mirror includes a tiltable mirror.

21. The spectrometer of claim 16 , wherein the MEMS mirror includes a movable mirror.