Packaging for compact object-scanning modules
The present disclosure is directed to compact packaging for optical MEMS devices, such as one- and two-dimensional beam scanners. An embodiment in accordance with the present disclosure includes a light source and a MEMS-based scanning element for steering at least a portion of the light provided by the light source in at least one dimension as an output light signal, as well as one or more optical elements for collimating and/or redirecting light within a sealed chamber defined by the elements of a housing. In some embodiments, the one or more optical elements include a reflective lens that collimates the light provided by the light source while simultaneously correcting phase-front error imparted by the scanning element while steering the output beam.
1. A scanner for steering a first output signal in at least one dimension, the scanner comprising:
a light source configured to provide a first light signal;
a first element configured to receive the first light signal and provide a first portion of the first light signal as a collimated beam;
a scanning element that is a MEMS-based scanning element, the scanning element including a first actuator operative for steering the first portion in a first dimension, wherein the first actuator is a thermal actuator; and
a housing that includes a substrate, a body, and a cover having a thickness, the cover comprising a first material that is substantially transparent for the first portion, wherein the substrate, body, and cover collectively define a sealed chamber that contains the light source and the scanning element;
wherein the first output signal includes the first portion.
2. The apparatus of claim 1 wherein the scanning element is operative for steering the first portion in two dimensions.
3. The apparatus of claim 1 wherein the scanning element includes the first element.
4. The apparatus of claim 1 wherein the first element is selected from the group consisting of a mirror, a diffractive optical element (DOE), and a prism.
5. The apparatus of claim 1 wherein the first actuator is an isothermal actuator.
6. The apparatus of claim 1 wherein the first element is disposed on a first surface of the cover.
7. The apparatus of claim 6 wherein the first surface is outside the chamber.
8. The apparatus of claim 7 wherein the first element, the light source, and the scanning element are arranged to define an optical path that includes a plurality of light-path portions that transit the thickness of the cover.
9. The apparatus of claim 1 further comprising a second element configured to distribute the first portion into a plurality of beamlets that includes the first output signal.
10. The apparatus of claim 1 further comprising:
a second element that is configured to split the first light signal into a plurality of second light signals; and
a plurality of scanning elements that includes the first scanning element, wherein each scanning element of the plurality thereof is configured to steer a different second light signal of the plurality thereof in at least one dimension, and wherein the plurality of second light signals includes the first portion.
11. The apparatus of claim 1 wherein the scanning element includes a first region that is configured to direct a second portion of the first light signal along a direction that is unaligned with the first portion.
12. The apparatus of claim 1 further comprising a second element and a detector, wherein the second element is configured to direct at least some of the first portion toward the detector as a calibration signal when the first portion is aligned with a first direction.
13. The apparatus of claim 12 wherein the detector is located outside of the housing.
14. The apparatus of claim 13 wherein cover includes a sidewall, and wherein the calibration signal transits the sidewall.
15. The apparatus of claim 1 wherein the first element includes a reflective lens that has a focal point, and wherein the first element receives the first light signal from the light source, and further wherein the first element and light source are arranged such that the light source is displaced from the focal point by a first distance that is a non-zero distance.
16. The apparatus of claim 15 wherein the first distance is based on a curvature of the scanning element.
17. The apparatus of claim 1 wherein the cover is configured to inhibit passage of a second portion of the first light signal through the cover, wherein the first portion is characterized by a first wavelength and the second portion is characterized by a second wavelength.
18. A scanner for steering a first output signal in at least one dimension, the scanner comprising:
a light source configured to provide a first light signal;
a first element configured to receive the first light signal and provide a first portion of the first light signal as a collimated beam;
a scanning element that is a MEMS-based scanning element, the scanning element being operative for steering the first portion in a first dimension; and
an integrated-circuit-chip package that includes a substrate, a body, and a cover having a thickness, the cover comprising a first material that is substantially transparent for the first portion, wherein the substrate, body, and cover collectively define a low-profile housing that encloses a sealed chamber that contains the light source and the scanning element;
wherein the first output signal includes the first portion.
19. The scanner of claim 18 wherein the sealed chamber contains a vacuum.
20. A scanner for steering a first output signal in at least one dimension, the scanner comprising:
a light source configured to provide a first light signal;
a first element configured to receive the first light signal and provide a first portion of the first light signal as a collimated beam;
a scanning element that is a MEMS-based scanning element, the scanning element being operative for steering the first portion in a first dimension, wherein the scanning element is configured to at least partially collimate the first portion; and
an integrated-circuit-chip package that includes a substrate, a body, and a cover having a thickness, the cover comprising a first material that is substantially transparent for the first portion, wherein the substrate, body, and cover collectively define a low-profile housing that encloses a sealed chamber that contains the light source and the scanning element;
wherein the first output signal includes the first portion.