Optics: measuring and testing – Position or displacement
Reexamination Certificate
2007-01-09
2007-01-09
Toatley, Jr., Gregory J. (Department: 2877)
Optics: measuring and testing
Position or displacement
C356S141500, C250S206100, C250S206200, C250S216000
Reexamination Certificate
active
10705853
ABSTRACT:
A sensor for determining the angular position of a radiating point source in two dimensions includes a mask encoded in two skewed directions with waveforms consisting of several frequencies in prescribed patterns. The frequency spectra of the received detector patterns are computed. In order to facilitate such computations, the constituent frequencies are separated so as to be distinguished in the Fast Fourier Transform (FFT). Each of the frequency patterns that are coded on the variable transmissivity mask consists of a series of low frequencies followed by a series of variable frequencies, and a series of high frequencies. The variable frequencies exhibit frequency changes responsive to various image positions. The low and high frequencies are responsive in phase to variations in image position. The frequency variations in the variable frequencies are used to indicate coarse position while the phases of the fixed low and high frequencies are used to indicate medium and fine position. In a second embodiment, the mask pattern is formed by a first pattern including low variable and high frequency components, a second pattern with fixed low and high frequency components, and a third pattern with variable frequency components. The method of determining position is also disclosed.
REFERENCES:
patent: 4092072 (1978-05-01), Ellis
patent: 4314761 (1982-02-01), Reymond et al.
patent: 4794245 (1988-12-01), Auer
patent: 4810870 (1989-03-01), Tsuno et al.
patent: 4857721 (1989-08-01), Dunavan et al.
patent: 4874937 (1989-10-01), Okamoto
patent: 4999483 (1991-03-01), Okamoto
patent: 5483060 (1996-01-01), Sugiura et al.
patent: 5499098 (1996-03-01), Ogawa
patent: 5757478 (1998-05-01), Ma
patent: 6274862 (2001-08-01), Rieger
Duling Alec
Odell Don
Ascension Technology Corporation
Nguyen Sang H.
Spiegel H. Jay
Toatley , Jr. Gregory J.
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