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
Controller with screen
Avalanche photodiodes having accurate and reproductible amplification layer
Character input device and program for displaying next word candidates based on the candidates' usage history
Deceleration dependent shift control
Vehicle driving assistance apparatus
Energy drink package
Heterocyclic compounds as CCR2B antagonists
  Randomly Featured Patents
Image forming apparatus that judges lifetime of photosensitive unit
Rechargeable battery which combats shape change of the zinc anode
Process for the extraction of a compound by a fluorocarbon compound
Method of manufacturing a plastic aerosol container having plastic end closures
Coalescence separator with changeable coalescence element
Airbag device
Fishing reel cleaning solution
HF alkylation process with acid regeneration
Quick lock in parallel and angle plate system for machining vise