Invention Grant
- Patent Title: LED control using modulation frequency detection techniques
- Patent Title (中): LED控制采用调制频率检测技术
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Application No.: US12874201Application Date: 2010-09-01
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Publication No.: US08258709B2Publication Date: 2012-09-04
- Inventor: Philip E. Moskowitz
- Applicant: Philip E. Moskowitz
- Applicant Address: US MA Danvers
- Assignee: Osram Sylvania Inc.
- Current Assignee: Osram Sylvania Inc.
- Current Assignee Address: US MA Danvers
- Agent Robert F. Clark; Andrew Martin
- Main IPC: H05B37/02
- IPC: H05B37/02

Abstract:
In one embodiment, the present disclosure provides a method for controlling a plurality of LED channels. The method includes receiving an LED brightness signal having a plurality of superimposed pulse width modulated (PWM) brightness signals each having a duty cycle and amplitude at a unique modulation frequency, each PWM brightness signal being proportional to the brightness of a respective LED channel. The method also includes determining a pulse area of each PWM brightness signal at each respective unique frequency. The pulse area is proportional to the product of the amplitude and the duty cycle. The method also includes generating pulse area signals proportional to the respective pulse area and comparing the respective pulse area signals to user defined and/or preset photometric values to generate respective error signals proportional to the difference between the respective pulse area signals and the user defined and/or preset photometric values.
Public/Granted literature
- US20120049743A1 LED CONTROL USING MODULATION FREQUENCY DETECTION TECHNIQUES Public/Granted day:2012-03-01
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