The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 26, 2001
Filed:
Nov. 20, 1998
John Wu, Taipei, TW;
Lite-On Electronics, Inc., Taipei, TW;
Abstract
A detecting device of an encoder is disclosed. The detecting device comprises a photodetector and a detection circuit. The photodetector has three active areas, and the detection circuit compares each two of the electric signals outputted from the three active areas for deriving a digital waveform with a desired phase and duty cycle. Thus, the digital signal may be correctly decoded into a vector data by a digital circuit in the next stage. The shift of signal level induced from the decay of LED may be avoided. The defect of a prior art optomechanical encoder is also avoided. In the prior art encoder, a fixed voltage is used as a comparing voltage and thus the encoded signal could be too strong or too weak due to the variation of the sensitivities of different photodetectors and the difference in the light intensities of the LEDs.