3807879 is referenced by 2 patents and cites 2 patents.

A quantized indicating unit has a circuit path for current flow. A controllable constant current source is connected in the circuit path for current flow and has a control circuit. The current source is characterized in that bias signals at the control circuit varies the amount of current flowing therethrough. A controllable variable impedance is coupled as a load circuit in the circuit path for current flow. A bias establishing circuit is provided for the control circuit and includes a plurality of impedances and means are provided for selectively coupling any one of the impedances to the control circuit, thereby establishing the bias on the control circuit. Scanning circuitry repeatedly and sequentially scans through a sequence of states. The coupling means responds to each different one of the states for coupling at least one different impedance to the control circuit, thereby causing for each of the states a different bias signal on the control circuit and a signal on the variable impedance corresponding to the amount of current flowing through the variable impedance. A source of a reference signal is provided together with a comparing circuit for comparing the signal with the reference signal. An indicating element is provided for each of the impedances and means are provided for coupling to the scanning circuit and the comparing circuit and is operative in synchronism with the scanning of the scanning circuit for responding to each correspondence detected by the comparing circuit for switching an indicating element into an indicating condition which indicating element corresponds to the impedance that is coupled to the control circuit at the detected correspondence.

Title
Photometer comprising quantized indication arrangement
Application Number
05/289,983
Publication Number
3807879
Application Date
September 18, 1972
Publication Date
April 30, 1974
Inventor
Mori Chiharu
Agent
Christie Parker & Hale
Assignee
Asahi Kagaku Kogyo Kabushiki Kaisha
IPC
H01j 39/12
G01j 01/44
H03M 01/00
G03B 17/18
G01J 01/44
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