Color Range Images Captured by a Four-Phase CMOS Image Sensor

• Published in: IEEE transactions on electron devices Vol. 58; no. 3; pp. 732 - 739
• Main Authors: LIN, Dong-Long, WANG, Ching-Chun, WEI, Chia-Ling
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.03.2011; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; CMOS; CMOS image sensors; CMOS integrated circuits; Color; Color range image; complementary metal-oxide-semiconductor (CMOS) image sensor; Design. Technologies. Operation analysis. Testing; Electric potential; Electronics; Exact sciences and technology; Frequency modulation; General (including economical and industrial fields); Image color analysis; Imaging devices; Integrated circuits; Microelectronic fabrication (materials and surfaces technology); Pixel; Pixels; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Semiconductors; Sensors; three-dimensional (3-D); time of flight (TOF); Voltage; CMOS image sensors; time of flight (TOF); Actuation voltage; Voltage control; Color range image; Three-dimensional displays; Microelectronic fabrication; Continuous wave; three-dimensional (3-D); Complementary MOS technology; Multilevel system; complementary metal-oxide-semiconductor (CMOS) image sensor; Measurement sensor; Time measurement; Switching; Color image; Light emitting diode; High voltage; Electronics industry; Time of flight method; Tridimensional image; Distance measurement; Blue light; Green light; Reflectance
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2010.2095857

As 3-D displays become more common, the demand for 3-D-related products is rapidly increased. Three-dimensional image sensors based on the time-of-flight (TOF) technique are one of these products and are applied to many applications. In this paper, a new pixel based on the continuous-wave modulation method was proposed to measure the TOF and was embedded in a test complementary metal-oxide-semiconductor (CMOS) image sensor. Compared with other range imagers, no complex control signals, high operating voltage, or multilevel control voltages are needed in this pixel. The chip, with 92 × 30 pixels, was fabricated using the Taiwan Semiconductor Manufacturing Company's 0.18-μm CMOS standard process, and a time-switched color measurement was applied to this rangeflnder system. A pulse train of red, green, and blue lights is emitted sequentially from a light-emitting diode array. The distance is easily calculated from the phase differences, and the color information is estimated using the difference in reflection coefficients under a different light. The measured distance and color are compared with the actual dis tance and color-corrected images. A color range image with a distance error of 3.56 cm and an L*a*b color difference of 40.23 can be observed. This rangefinder system provides a new perspective to capturing a colored range image.