On-car stray-light testing cart

Abstract

Methods, systems, and apparatus for a stray-light testing apparatus. In one aspect, the apparatus includes an optical assembly including a spatially extended light source and one or more optical elements arranged to direct light from the spatially extended light source along an optical path, a moveable frame supporting the optical assembly including one or more adjustable alignment features for guiding positioning of the stray-light testing apparatus relative to an onboard camera on a vehicle, and a shrouding mechanism attached to the frame and positioned on the frame such that, when the stray-light testing apparatus is aligned relative to the onboard camera on the vehicle and the optical path of the optical assembly is within the field of view of the onboard camera, ambient light exposure for the onboard camera is below a threshold.

What is claimed is: 
     
         1 . A stray-light testing apparatus comprising:
 an optical assembly comprising a light source and two rotational stages, each rotational stage supporting one or more optical elements, wherein the optical assembly is arranged to direct light from the light source along an optical path, and wherein the two rotational stages adjust an angle of incidence of the light from the light source along the optical path with respect to a field of view of an onboard camera of an automobile when the stray-light testing apparatus is aligned relative to the onboard camera on the automobile;   a frame supporting the optical assembly; and   a shroud attached to the frame and arranged to cover an area of the optical path.   
     
     
         2 . The apparatus of  claim 1 , wherein, when the stray-light testing apparatus is aligned relative to the onboard camera on the automobile, the shroud blocks ambient light exposure from the onboard camera. 
     
     
         3 . The apparatus of  claim 1 , wherein the light source is a spatially-extended light source. 
     
     
         4 . The apparatus of  claim 3 , wherein the two rotational stages adjust the angle of incidence of the light from the light source along the optical path with respect to the field of view of the onboard camera over a range of incident angles. 
     
     
         5 . The apparatus of  claim 1 , wherein the light source is a first light source, and wherein the optical assembly further comprises a second light source. 
     
     
         6 . The apparatus of  claim 5 , wherein the optical assembly is arranged to selectively direct light from the first light source or second light source along the optical path. 
     
     
         7 . The apparatus of  claim 5 , wherein, when the stray-light testing apparatus is aligned relative to an onboard camera on an automobile, the second light source is arrange with respect to the frame to direct light along a second optical path with respect to a field of view of a second onboard camera. 
     
     
         8 . The apparatus of  claim 5 , wherein the first light source and the second light source are each selected from a group consisting of a light-emitting diode broad spectrum 6500 k source, an infrared 850 nanometer light source, a hyper-spectral source, and a xenon source. 
     
     
         9 . The apparatus of  claim 5 , wherein the optical assembly further comprises a light pipe arranged with respect to the first light source and the second light source to selectively direct light from the first light source or second light source along the optical path. 
     
     
         10 . The apparatus of  claim 1 , further comprising a plurality of filters selected from a group consisting of neutral density filters, band-pass filters, interference filters, dichroic filters, and absorptive filters. 
     
     
         11 . The apparatus of  claim 1 , wherein the frame is affixed to one or more of a floor, ceiling, and wall of a testing area including the stray-light testing apparatus. 
     
     
         12 . The apparatus of  claim 1 , further comprising a controller in data communication with i) the light source and operable to provide instructions to the light source, and ii) the two rotational stages and operable to provide instructions to the two rotational stages. 
     
     
         13 . A method for determining stray-light performance of an onboard camera of an automobile, the method comprising:
 positioning a stray-light testing apparatus relative to the onboard camera on the automobile to direct light from a light source of the stray-light testing apparatus along an optical path;   for a plurality of angles of incidence of light from the light source along the optical path with respect to a field of view of the onboard camera that are selectable by adjusting an orientation of two rotational stages of the stray-light testing apparatus:
 selecting an angle of incidence of the plurality of angles of incidence of light from the light source along the optical path with respect to a field of view of the onboard camera; 
 exposing the onboard camera to the light from the light source at the angle of incidence; and 
 capturing image data by the onboard camera while exposing the onboard camera to the light from the light source at the angle of incidence; and 
   determining, based on the captured image data, performance metrics for the onboard camera.   
     
     
         14 . The method of  claim 13 , further comprising:
 selecting, from two or more light sources of the stray-light testing apparatus, the light source.   
     
     
         15 . The method of  claim 14 , wherein the light source is selected from a group consisting of a light-emitting diode broad spectrum 6500 k source, an infrared 850 nanometer light source, a hyper-spectral source, and a xenon source. 
     
     
         16 . The method of  claim 14 , wherein selecting the light source from two or more light sources comprises selectively directing light from the light source of the two or more light sources along the optical path via a light pipe. 
     
     
         17 . The method of  claim 13 , further comprising:
 providing, by a controller of the stray-light testing apparatus and to the onboard camera, instructions to select an exposure of the onboard camera; and   collecting, by the controller, the image data.   
     
     
         18 . The method of  claim 13 , further comprising:
 determining, from the performance metrics, a source of stray-light conditions for the onboard camera; and   in response, generating stray-light condition compensation for the onboard camera.   
     
     
         19 . The method of  claim 18 , wherein stray-light condition compensation comprises compensation for a glare and/or saturation by a light source in a field of view of the onboard camera. 
     
     
         20 . The method of  claim 13 , wherein positioning the stray-light testing apparatus relative to the onboard camera on the automobile further comprises aligning a second light source of the stray-light testing apparatus with respect to the onboard camera of the automobile to direct light along a second optical path with respect to a field of view of a second onboard camera.