Naohisa Mukozaka

A high-speed CMOS image sensor with profile data acquiring function

We have developed a Profile Imager aimed at high-speed automatic target tracking. The Profile Imager can perform both target tracking within a 512 /spl times/ 512-pixel entire image area and acquisition of partial images simultaneously and independently. Experimental results of capturing 128 /spl times/ 128-pixel partial images of an automobile license plate at 1620 frames/s are presented. In addition, results of integrating 89 partial images demonstrate the capability of the device as a high-speed, high-resolution, high-dynamic-range image tracker. A 0.6-/spl mu/m two-poly three-metal CMOS process is used to implement a 13.0 mm /spl times/ 14.3 mm imager.

A 3.2 kHz, 14-Bit Optical Absolute Rotary Encoder With a CMOS Profile Sensor

We have developed a 3.2 kHz, 14-bit optical absolute rotary encoder system using a profile sensor and a slit disc. The profile sensor, which we have designed for this purpose, is a unique CMOS area image sensor aimed at high-speed position detection of X and Y axes. Y axis profile data from the profile sensor is used for recognition of an index code on the slit disc, and X axis profile data is used for position detection of the index code. This combination of two-axis information enables high resolution even with a small number of index codes (64 indexes) and a small amount of digital calculations. Experimental results show that this system can detect rotation with an angular resolution of 14 bits (0.022deg) and a maximum detection speed of 3.2 kHz.

A 256/spl times/256 compact CMOS image sensor with on-chip motion detection function

A 256/spl times/256 CMOS passive pixel image sensor with especially equipped simple switches, which enables motion detection, is implemented. Each pixel consists of a simple combination of a photodiode and an address switch. Photocharge generated at each pixel is converted to voltage by means of a column charge amplifier array, and motion detection has been realized with utilizing the photodiode as a frame memory. Its output is transformed to a digital value with a 128 array 8-bit analog-to-digital (A/D) converter. Simultaneously, fixed pattern noise is suppressed by utilizing A/D conversion as the CDS circuit. Due to its simple structure, more than 70% fill factor ratio has been realized. The extracted motion detection results can be displayed digitally at 128 frames per second by means of 128 A/D converter arrays.

A high-speed, profile data acquiring image sensor

A profile imager for high-speed automatic target tracking has the capability of executing both target-tracking control from a 512/spl times/512 image array of 20 /spl mu/m/spl times/20 /spl mu/m pixels and the acquisition of a sub-array, simultaneously. 128/spl times/128 partial images of an automobile license plate can be captured at 1620f/s. A 0.6 /spl mu/m 3M2P CMOS process is used to implement the 13.0mm/spl times/14.3mm imager.

A 3.2 kHz, 13-bit Optical Absolute Rotary Encoder with a CMOS Profile Sensor

We have developed a 3.2 kHz, 13-bit optical absolute rotary encoder system using a profile sensor and a slit disc. The profile sensor, which we have designed for this purpose, is a unique CMOS area image sensor aimed at highspeed position detection of X and Y-axes. The profile data of Y-axis from the profile sensor is used for recognition of an index code number of a slit disc and that of X-axis is used for position detection of the index code. This combination of both axes information enables to achieve high resolution even with less number of index codes (64 indexes) and small amount of digital calculations. Experimental results assure that this system can detect 13 bit angle resolution (0.044 degree) and the speed of detection reaches at maximum 3.2 kHz.

Column parallel vision system: CPV

We have designed and constructed a column parallel vision (CPV) system to realize an intelligent and general purpose image processing system with higher frame rate within 1 millisecond. The system consists of an original designed photo detector array (PDA) with high frame rate, a parallel processing unit with fully parallel processing elements (PEs), and a controller for PDA and PEs. The column parallel architecture enables the PDA 1 millisecond frame rate with 256 analog levels which is required for industrial image processing and measurements. The parallel processing unit has been fabricated by using FPGAs and has 128 X 128 PEs to perform the fully parallel image processing. The PEs have the S3PE architecture which has SIMD type parallel processing flow, and was constructed only 500 transistors suitable for integration in future. Since the PEs are operated by control signal from the controller, we can achieve desired image processing task to the system by changing the software. We have demonstrated that the system can be worked as a tracking system. The experimental results show the system was realized high speed feedback loop as 1000 frame/s including the tracking operation with noise reduction, matching (self-window algorithm) and moment calculation.

1 kHz measurement by using intelligent vision system - stereovision experiment on column parallel vision system: CPV4 -

We have designed and constructed a column parallel vision (CPV) system to realize an intelligent and general-purpose image processing system with higher frame rate within 1 millisecond. In this paper, we have constructed a compact CPV system (CPV4) by using newly designed and developed PE-array chip integrating 128times128 processing elements for fully parallel processing. By using the PE-array chip, we can construct a compact CPV system by three semiconductor chips of sensor, PE-array and controller. We have demonstrated the CPV-4 for stereovision by using two-camera input setup and high-speed computing power of matching operation. The results of stereovision experiment show the CPV-4 has adequate processing speed for depth map calculation with several advantages such as a higher-clock rate operation and lower electric power consumption in compact module. This improvement can let a system fit wider applications, such as robot-eye, FA-inspection, man-machine interface, that require the characteristics of high-speed image capturing, processing and compactness.