Output circuit of a charge-coupled device

Claim 1

A detection system for detecting information using a charge-coupled device, comprising: a charge-coupled device for detecting information, said charge-coupled device being supplied with a clock pulse having a predetermined frequency and producing an output signal pulse including a signal component that corresponds to the information in response to each clock pulse; memory means for storing a set of orthogonal functions each having a frequency that is equal to or a multiple of the frequency of the clock pulse, said orthogonal functions being chosen such that any orthogonal function in the set produces a zero inner product with other orthogonal function in the set; and processing means supplied with the output signal pulse from the charge-coupled device sequentially in response to the clock pulse and further for reading out the orthogonal functions stored in the memory means, said processing means expanding each output signal pulse of the charge-coupled device into an orthogonal series using the orthogonal functions as a base of expansion, said orthogonal series involving a plurality of terms each characterized by a coefficient of expansion and a corresponding orthogonal function serving for the base; wherein said processing means extracts a term in the orthogonal series that corresponds to the signal component representing the information detected by the charge-coupled device as an output signal.

Claim 10

A method for eliminating noise from an output signal pulse produced sequentially by a charge coupled device in response to a clock pulse having a predetermined clock frequency, said output signal pulse representing information that is detected by the charge coupled device, comprising the steps of: filtering the output signal pulse to form a filtered output signal pulse such that signal components having a frequency that exceeds the clock frequency are substantially eliminated from the filtered output signal pulse; expanding said filtered output signal pulse obtained in said step of filtering the output signal pulse into an orthogonal series having a plurality of terms therein, each term comprising a coefficient of expansion; extracting a term that represents the information signal from said plurality of terms that are obtained in said step of expanding the filtered output signal pulse; and calculating as an output signal pulse a norm from the coefficient of expansion in the extracted term obtained in said step of extracting, said output signal pulse representing the information detected by the charge coupled device and from which the noise is eliminated.

Claim 11

A method for eliminating noise from an output signal pulse produced sequentially by a charge coupled device in response to a clock pulse having a predetermined clock frequency, said output signal pulse representing information that is detected by the charge coupled device, comprising the steps of: filtering the output signal pulse to form a filtered output signal pulse such that signal components having a frequency that exceeds the clock frequency are substantially eliminated from the filtered output signal pulse; expanding said filtered output signal pulse obtained in said step of filtering the output signal pulse into an orthogonal series having a plurality of terms therein, each term comprising a coefficient of expansion; extracting a term that represents the information signal from said plurality of terms that are obtained in said step of expanding the filtered output signal pulse; and calculating as an output signal pulse a norm from the coefficient of expansion in the extracted term obtained in said step of extracting, said output signal pulse representing the information detected by the charge coupled device and from which the noise is eliminated.