초록 ▼

A system for determining the range to an object utilizing a plurality of radiation responsive detectors arranged in groupings wherein a first grouping of detectors receives radiation from the object in a first pattern and the second grouping of detectors receives radiation from the object in a secon

A system for determining the range to an object utilizing a plurality of radiation responsive detectors arranged in groupings wherein a first grouping of detectors receives radiation from the object in a first pattern and the second grouping of detectors receives radiation from the object in a second pattern. The patterns move with respect to one another as the distance between the object and the system changes. The range is determined from a determination of the relative position of the patterns by computing where the patterns will coincide if the focusing lens of the system is moved. The output is a signal having a characteristic indicative of the desired direction of motion of the lens and a characteristic indicative of the amount of such motion necessary to produce a proper focus condition.

대표청구항 ▼

Apparatus for use with an auto focus system which includes lens means that produces first and second radiation distribution patterns of a scene to be focussed upon, the patterns being similar and in a first relative position when the lens means is in a proper focus position with respect to the scene

Apparatus for use with an auto focus system which includes lens means that produces first and second radiation distribution patterns of a scene to be focussed upon, the patterns being similar and in a first relative position when the lens means is in a proper focus position with respect to the scene, the patterns moving away from the first relative position in a first relative direction as the relative position of the scene and the lens means changes from the proper focus position in one direction and the patterns moving away from the first relative position in a second relative direction as the relative position of the scene and the lens means changes from the proper focus position in a direction opposite to the one direction comprising, in combination: a first plurality of radiation detectors positioned to receive the first radiation distribution pattern, each radiation detector in the first plurality of radiation detectors operable to produce an output indicative of the radiation received thereby; a second plurality of radiation detectors positioned to receive the second radiation distribution pattern, each radiation detector in the second plurality of radiation detectors operable to produce an output indicative of the radiation received thereby, each radiation detector in the second plurality of radiation detectors having a positionally corresponding radiation detector in the first plurality of radiation detectors so that, when the lens means is in a proper focus position, the output of each radiation detector in the second plurality of radiation detectors is substantially equal to the output of its positionally corresponding radiation detector in the first plurality of radiation detectors; shift register means connected to receive the outputs of the radiation detectors in the first and second plurality of radiation detectors and operable to shift the outputs of the radiation detectors in one of the plurality of radiation detectors with respect to the outputs of the positionally corresponding radiation detectors in the other of the plurality of radiation detectors; signal receiving means connected to the shift register means to receive the outputs of the radiation detectors in the first and second plurality of radiation detectors and to produce a plurality of consecutive outputs, Vi, in accordance with the expression [Figure] where N is the number of radiation detectors in the first plurality of radiation detectors, n is any number of 1 to N, a represents the output of individual radiation detectors in the first plurality of radiation detectors, b represents the output of individual radiation detectors in the second plurality of radiation detectors and i represents the number of shifts of the shift register from -N/2 to +N/2; difference means connected to the signal receiving means to receive each two consecutive values of Vi and to produce consecutive outputs, Di, representative of the difference therebetween; storage means connected to the difference means to receive and store the outputs Di; comparator means connected to the storage means to receive the latest value of Di and the largest Di value previously stored in the storage means and to produce an output DL representative of the largest Di compared; means connecting the comparator means to the storage means to substitute the DL output for the largest Di value previously stored in the storage means; and signal processing means connected to the storage means to receive the largest DL signal, Dm, when i=+N/2 and to produce an output, L.E., indicative of P(Vm/Dm+im) where P is a constant proportional to the distance between radiation detectors in the first and second plurality of radiation detectors, and Vm and im are the Vi and i values when the DL value is equal to Dm.