Paper
21 February 2007 Image sensor for object detection using modulated light
H. Taruki, A. Ohno, F. Ono, T. Hamamoto, T. Sasaki, T. Shirai, M. Sakai
Author Affiliations +
Abstract
We have been investigating a system to detect moving objects correctly at the place where luminous intensity is changing because of the influence of incident light such as sunlight, fluorescent light and car headlight. The object detection system consists of a smart image sensor and a modulated LED light, and it is possible to suppress the influence of the change of background light by using a different value between two image values when the LED light is turned on and off. Because the speed of modulation is high for accurate detection of moving objects, electric charges from a photodiode are distributed into two capacitors by switching in sync with the LED light in a pixel circuit of the sensor. Also, the sensor has a subtraction function by a current mirror circuit to reduce the same charges from two capacitors before saturation. By the frequent subtractions, it is possible to increase only the influence of the modulated light and reconstruct wide dynamic range images at outside of the sensor by using the information of subtractions and the voltage value of each capacitor.
© (2007) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
H. Taruki, A. Ohno, F. Ono, T. Hamamoto, T. Sasaki, T. Shirai, and M. Sakai "Image sensor for object detection using modulated light", Proc. SPIE 6501, Sensors, Cameras, and Systems for Scientific/Industrial Applications VIII, 65010H (21 February 2007); https://doi.org/10.1117/12.704645
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Modulation

Capacitors

Photodiodes

Image sensors

Light emitting diodes

Sensors

Mirrors

RELATED CONTENT


Back to Top