Eye safe optical modules
The present disclosure relates to a packaging approach for ensuring that high power optical modules incorporating VCSELs and VCSEL arrays remain eye safe. A VCSEL device or VCSEL package of the present disclosure may generally be configured certifying an optical device as eye safe such that the device is able to survive a single failure mode. In other embodiments, a multiple lens array is arranged above the VCSEL, which scatters the light into a wide range of angles such that a higher percentage of light will reach the photodetector located beside the VCSEL. In other embodiments according to the present disclosure, one or more methods and circuits are provided to detect and correct errors or failures caused by one or more unsafe conditions.
1. An optical element package, comprising:
at least one optical element arranged on a submount;
a window configured and arranged to allow light emitted from the optical element to pass through the window;
a plurality of micro lenses arranged on at least a portion of the window such that the light from the optical element contacts the plurality of micro lenses; and
a photodiode arranged on the submount beside the at least one optical element and offset from the plurality of micro lenses;
wherein a first portion of the light is transferred through the plurality of micro lenses, a second portion of the light is scattered back into the package, and a third portion of light is scattered laterally in the window and down towards the photodiode;
wherein a number of micro lenses in the optical element package exceeds a number of optical elements in the optical element package.
2. The optical element package of claim 1 , wherein the optical element comprises one or more VCSEL devices.
3. The optical element package of claim 1 , wherein the plurality of micro lenses are arranged in an irregular pattern.
4. The optical element package of claim 1 , wherein the plurality of micro lenses are arranged in a regular array pattern.
5. The optical element package of claim 1 , wherein the one or more micro lenses are positioned such that the majority of light from the optical element passes through the window.
6. The optical element package of claim 1 , further comprising a spacer arranged between the submount and the window.
7. The optical element package of claim 1 , wherein at least 20% of the light emitting from the optical element scatters back into the optical element package.
8. The optical element package of claim 1 , wherein the one or more micro lenses are arranged on the window so as to be aligned with a central axis of light emitted from the VCSEL device.
9. The optical element package of claim 1 , wherein a portion of the light emitted is scattered laterally, thereby increasing the eye safety of the device.