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

Image Number 3 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
Method for manufacturing photoelectric conversion device
External preparation composition for skin comprising ginseng flower or ginseng seed extracts
Inducement of organogenetic tolerance for pancreatic xenotransplant
Polarization-coupled ferroelectric unipolar junction memory and energy storage device
Process for the production of an acylation catalyst
Level shifter and method of using the same
Tailoring the band gap of solar cells made of liquid silane by adding germanium
  Randomly Featured Patents
Tumor suppressor gene P33ING2
Method and apparatus for automated trade transactions processing
Plate for connecting base splinters with bone shafts
Transport pack
Process for the preparation of aldehydes
Method and apparatus for temporarily suspending a network connection
Driven full-bridge inverter ballast
Mounting clamp for securing apparatus to outside of tie rod cylinder
Betatron with a contraction and expansion coil