Apparatus and method for multi configuration near eye display performance characterization

A method for performance characterization of mufti configuration near eye displays as a device under test (DUD by an optical apparatus, the optical apparatus including a viewfinder digital camera, the method comprising:

• aligning an optical axis of the optical apparatus with an optical axis of the DUT to establish an optical measurement axis, wherein the aligning comprises:
• forming a reference image of a field-of-view (FOV) measurement aperture illuminated by a lamp, wherein a first portion of a light illuminated by the lamp is reflected from a beamsplitter, collimated by a collimating lens and reflected back onto the beamsplitter, and a portion of the collimated light is captured as the reference image by the viewfinder digital camera,
• forming an actual image of the FOV measurement aperture by projecting a second portion of the light illuminated by the lamp from the beamsplitter onto the DUT and reflecting the second portion of the light by a mirror back onto said beamsplitter,
• projecting a third portion of the reflected second portion light onto the viewfinder digital camera by the beamsplitter, and
• capturing the third portion of the reflected second portion light by the viewfinder digital camera to form the actual image of the FOV measurement aperture,
• superimposing the reference image of the FOV measurement aperture and the actual image of the FOV measurement aperture to align the optical axis of the optical apparatus with the optical axis of the DUT to establish said optical measurement axis;
• defining a measurement area on a virtual image of the DUT;
• performing adjustments to transpose the captured image of the defined measurement area and a complete field of view of the view finder digital camera to establish alignment of the FOV measurement aperture to another area within the DUT scene field of view;
• turning off the lamp to allow only the virtual image of the DUT to be seen by the viewfinder digital camera;
• capturing an image of the defined measurement area and the complete field of view of the viewfinder digital camera, wherein the captured image of the defined measurement area and the captured image of the complete field of view of the viewfinder digital camera are both reflected from said beamsplitter;
• moving the lamp and the beamsplitter from the optical measurement axis so that none of the light passing through FOV measurement aperture is blocked from reaching a spectroradiometer;
• projecting the virtual image of the DUT onto the FOV measurement aperture;
• focusing an image of an entrance pupil of the optical apparatus onto a spatial mixer;
• collecting the virtual image from the spatial mixer onto a spectroradiometer;
• and
• performing spectroradiometric measurements on the captured image of the defined measurement area by the spectroradiometer.