Title:
【発明の名称】携帯通信端末
Document Type and Number:
Japanese Patent JP3177253
Kind Code:
B2
Abstract:
A proximity detector and ambient light monitor (PALM) is provided, comprising a light source for generating an optical composite signal, a light detector for providing a detected signal, a circuit for separating the ac component from the detected signal, and a switch for providing a control signal when the ac component is outside a preset range. The PALM further comprises an ambient light detector which also receives the detected signal and provides an ambient light level signal. The ambient light detection circuit rejects the signals that relate to the proximity monitoring and provides sufficient gain to overcome daylight filtering lens currently provided on the light detectors. The ambient light monitoring circuit provides either a continuous varying voltage proportional to the ambient light, or a simple binary signal indicating that the light is above a threshold.
Inventors:
Kohi Ross George
Application Number:
JP51874698A
Publication Date:
June 18, 2001
Filing Date:
October 09, 1997
Export Citation:
Assignee:
NORTEL NETWORKS LIMITED
International Classes:
G01V8/10; G01J1/00; G01J1/18; H01J40/14; H03K17/78; H03K17/94; H03K17/945; H04M1/60; H04W88/02; H04M1/73; (IPC1-7): G01V8/10; H03K17/78; H04M1/60; H04Q7/38
Other References:
【文献】欧州特許出願公開572009(EP,A1)
【文献】独国特許出願公開3518025(DE,A1)
【文献】独国特許出願公開3518025(DE,A1)
Attorney, Agent or Firm:
Yoshiki Hasegawa (2 outside)