Resources Contact Us Home
Reading signal processing circuit in optical information reproducing apparatus

Image Number 6 for United States Patent #5164933.

In this invention, a reading signal detected by a photodetector is input into two differentiating circuits of different differential constants. The first differentiating circuit differentiates the reading signal with the differential constant larger than that of, for example, the second differentiating circuit and lowers the level of the noise component present as mixed in the reading signal. The first comparing circuit removes the noise component, for example, below the threshold value. The second differentiating circuit differentiates the reading signal with the differential constant converting the peak point of the reading signal, for example, of the above mentioned photodetector to a zero crossing point. The second comparing circuit compares the differential signal of the above mentioned differentiating circuit with the threshold value set, for example, on the zero level and makes the output signal rise, for example, in the center position of an information pit. A bivalued signal logical circuit obtains a bivalued signal made by bivaluing the reading signal from the respective output signals of the first and second comparing circuits.

  Recently Added Patents
Multi-touch recognition resistive touch screen for recognizing multi-touch coordinates through capacitor charging time
Power converter and method of power conversion
Multi-user remote health monitoring system with biometrics support
Plants and seeds of hybrid corn variety CH260114
Sterilizable film for aseptic packaging
Use of emerging non-volatile memory elements with flash memory
Optical module for a microlithography objective including holding and supporting devices
  Randomly Featured Patents
Method of selectively aligning and positioning nanometer-scale components using AC fields
Transfer of high temperature wafers
Method and apparatus of multiplejunction solar cell structure with high band gap heterojunction middle cell
Method for discriminating anodal and cathodal capture
Rotary drilling jar
Clothes hanger
Apparatus for fabricating a box-like article
Device for machining components, in particular of a vehicle body
Storage device utilizing a differentially permeable membrane to control gaseous content
Chimeric IgE polypeptides and host cells