Testing light transmitting articles
AssigneeBritish Aerospace Public Limited Company
InventorRoy S. Kalawsky
Life of this patent
Estimating the term…
Abstract
A disclosed canopy testing using an area imaging device, e.g. a T.V. camera, to view a scene, a cross-hatch pattern say, through the canopy. The viewed image is digitized and stored and a computer evaluates the target image by comparing the apparent positions of its features with their real positions and/or by sensing deviations from straightness of the pattern lines. In a development, a polarimeter or polarization sensitive camera is used to test for hazing and curvature defects.
Claims12
A method of testing the optical quality of a light transmitting article to be tested, comprising the steps of:
- forming a signal representative of an image of a two-dimensional pattern viewed through the article to be tested;
- storing a series of digital signals representative of respective pixels of said image;
- evaluating said digital signals to sense the presence of predetermined features of the pattern in said image;
- calculating spacial deviations in said features due to the presence of said article;
- and
- producing an indication of defects in said optical quality which is proportional to a magnitude of said spatial deviations.
Apparatus for testing the optical quality of a light transmitting article, comprising:
- means for presenting a two-dimensional target pattern;
- image sensor means positioned for viewing said pattern;
- support means for supporting said article between said pattern presenting means and said image sensor means;
- digitizer means, connected to said image sensor means, for forming a series of digital signals representative of respective pixels of the image received by the image sensor means;
- frame storing means, connected to the digitizer means, for storing said digital signal;
- computer means, connected to the frame storing means, for processing said signals to calculate a spacial deviation of predetermined features of the pattern due to the presence of said article;
- and
- indicating means for producing an indication of defects in said optical quality proportional to the magnitude of said spatial deviations.
A method for testing the optical quality of a light transmitting article, comprising the steps of:
- forming a video signal indicative of an optical image as viewed by an area imaging device through said article;
- producing first parameters by comparing said video signal against second parameters indicative of a view which would be seen by said device if the article were not present;
- and
- producing an indication of defects in said optical quality proportional to the magnitude of differences between the video signal and said second parameters.
Apparatus for testing the optical quality of a transparent article, the apparatus comprising:
- an area imaging device for forming a video signal indicative of an optical image viewed by the device via said article;
- computer means for checking said video signal against parameters indicative of the view which would be seen by the device if the article were not present;
- and
- output means for providing an indication of discrepancies between the video signal and said parameters proportional to a magnitude of said discrepancies.
Dependencies are inferred from the claim text.