Stray-light testing station
Methods, systems, and apparatus, for a stray-light testing station. In one aspect, the stray-light testing station includes an illumination assembly including a spatially extended light source and one or more optical elements arranged to direct a beam of light from the spatially extended light source along an optical path to an optical receiver assembly including a lens receptacle configured to receive a lens module and position the lens module in the optical path downstream from the parabolic mirror so that the lens module focuses the beam of light from the spatially extended light source to an image plane, and a moveable frame supporting the optical receiver assembly including one or more adjustable alignment stages to position the optical receiver assembly relative to the illumination assembly such that the optical path of the illumination assembly is within a field of view of the optical receiver assembly.
1. An apparatus comprising:
an illumination assembly comprising an extended light source and one or more optical elements arranged to direct a beam of light from the extended light source along an optical path;
an optical receiver assembly comprising a sensor and a lens receptacle configured to receive a lens module comprising one or more lenses and configured to position the lens module in the optical path so that the lens module focuses the beam of light from the extended light source to an image plane of the sensor; and
a moveable frame supporting the optical receiver assembly and/or the illumination assembly, the moveable frame comprising one or more adjustable alignment stages, wherein the adjustable alignment stages are configured to adjustably position the optical receiver assembly relative to the illumination assembly such that the beam of light along the optical path from the illumination assembly is adjustably incident on the optical receiver assembly for a range of angles of incidence between the illumination assembly and a field of view of the lens module of the optical receiver assembly.
2. The apparatus of claim 1 , wherein the lens module is an automotive lens module.
3. The apparatus of claim 1 , wherein the range of angles of incidence comprises +/−90 degrees with respect to a vertical axis and/or horizontal axis of the lens module.
4. The apparatus of claim 1 , wherein the range of angles of incidence comprises a first range of angles of incidence and a second, different range of angles of incidence.
5. The apparatus of claim 1 , further comprising:
a motor coupled to the moveable frame and operable to adjust a position of the one or more adjustable alignment stages of the moveable frame; and
a control unit in data communication with the illumination assembly, the optical receiver assembly, and the motor, and operable to perform operations of measuring a performance metric.
6. The apparatus of claim 1 , wherein the one or more adjustable alignment stages comprise at least two adjustable alignment stages, and wherein each of the adjustable alignment stages is independently adjustable with respect to each other adjustable alignment stage.
7. The apparatus of claim 1 , wherein the one or more adjustable alignment stages are adjustable through a yaw and/or roll with respect to the optical path to adjust an angle of incidence of a range of angles of incidence of the optical path on a lens module received by the lens receptacle.
8. The apparatus of claim 1 , wherein the beam of light from the extended light source incident on the lens module comprises a collimated beam of substantially uniform intensity across a diameter of the lens module.
9. The apparatus of claim 8 , wherein the extended light source is configured such that the beam of light overfills the lens module.
10. A method for determining a performance metric of an optical receiver assembly comprising:
for each angle of incidence of a plurality of angles of incidence of a beam of light from an illumination assembly onto an optical receiver assembly:
aligning, using one or more alignment stages, the optical receiver assembly and/or the illumination assembly to the angle of incidence,
wherein the illumination assembly comprises an extended light source and one or more optical elements arranged to direct the beam of light from the extended light source along an optical path, and the optical receiver assembly comprises a sensor and a lens receptacle configured to receive a lens module comprising one or more lenses and configured to position the lens module in the optical path downstream from the illumination assembly, and
wherein aligning the optical receiver assembly and/or the illumination assembly comprises focusing the beam of light from the extended light source of the illumination assembly to an image plane of the sensor of the optical receiver assembly;
exposing the optical receiver assembly to the beam of light from the extended light source at the angle of incidence;
capturing image data by the sensor of the optical receiver assembly while exposing the optical receiver assembly to the beam of light at the angle of incidence; and
determining, based on the captured image data for the plurality of angles of incidence, the performance metric for the optical receiver assembly.
11. The method of claim 10 , wherein determining the performance metric comprises:
determining a stray-light performance of the optical receiver assembly over the plurality of angles of incidence within a field of view of the optical receiver assembly.
12. The method of claim 10 , further comprising:
for each of the plurality of angles of incidence: selecting a first light intensity for the extended light source from a plurality of different light intensities, wherein selecting the first light intensity of the plurality of different light intensities from the extended light source comprises attenuating the beam of light from the extended light source using a neutral density filter.
13. The method of claim 10 , wherein aligning the optical receiver assembly and/or the illumination assembly comprises:
providing control instructions by a control unit in data communication with a motor coupled to a moveable frame and operable to adjust a position of the one or more alignment stages of the moveable frame.
14. The method of claim 10 , wherein aligning the optical receiver assembly and/or the illumination assembly comprises adjusting the alignment stages in one or more degrees of freedom to position the optical receiver assembly and/or the illumination assembly over a range of angles.
15. The method of claim 10 , wherein determining the performance metric comprises determining a spread of the beam of light from a center point of the extended light source at each angle of incidence of the plurality of angles of incidence.
16. The method of claim 15 , wherein determining the performance metric further comprises:
determining, at each of the plurality of angles of incidence, a respective spread of the beam of light from the center point of the extended light source for a plurality of different light intensities.
17. The method of claim 10 , wherein determining the performance metric comprises determining a glare spread function for the optical receiver assembly.
18. The method of claim 10 , wherein determining the performance metric comprises determining a rejection ratio for the optical receiver assembly.
19. The method of claim 10 , wherein the plurality of angles of incidence comprises a range of angles of incidence including +/−90 degrees with respect to a vertical axis and/or horizontal axis of the optical receiver assembly.
20. The method of claim 10 , wherein determining the performance metric of the optical receiver assembly comprises determining the performance metric of an automotive lens module.