Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : Tower Semiconductor -- Ignore unavailable to you. Want to Upgrade?

To: Ed Hawkins who wrote (1835)	11/30/1999 9:14:00 PM
From: yosi s	Read Replies (1) \| Respond to of 1853

CMOS IMAGING getting hot. eetimes.com CMOS image sensor goes mainstream By Chappell Brown EE Times (11/30/99, 5:54 p.m. EDT) FREMONT, Calif. ? Logitech Inc.'s recently announced upgrade strategy for its QuickCam Express digital camera line has pulled CMOS pixel sensor technology one step closer to the mainstream commercial market. The company will be replacing charge-coupled device (CCD) sensors in the cameras with a 352 x 288-pixel CMOS image sensor from Photobit Inc. (Pasadena, Calif.). Photobit was formed by engineers from the Jet Propulsion Laboratory, which had developed the sensor technology for space craft. Only a few years ago, CMOS "active-pixel" technology was still in the research stage. Photobit began marketing CMOS image sensors based on the technology last year, and now has four products. In addition to the QuickCam sensor, Photobit also offers a VGA-format 640 x 480-pixel sensor, a high-definition television format chip and a high-speed 500-frame/second megapixel video chip. NASA was interested in the approach because the imaging chips consume much less power than CCDs, and since they are CMOS-compatible, it is possible to integrate image-processing circuitry to simplify camera design. Those advantages, along with lower cost, also have made the technology attractive to consumer product vendors. The new sensor, Photobit's PB-0100, will allow Logitech to enhance the performance of its QuickCam design, which captures video for low-bandwidth communications over phone lines and the Internet. The imager is designed for small-format applications such as video cell phones or handheld scanners. The chip includes digital signal processing circuitry to enhance the performance of the sensor. The on-chip circuitry also converts the output directly into full-frame, 8-bit digital video at 39 frames/second. The chip can also perform other imaging functions that usually require optical and mechanical subsystems. Through the use of a digital serial interface, for example, it can be programmed via digital signal processing for pan, tilt and zoom functions.

To: Ed Hawkins who wrote (1835)	12/16/1999 8:48:00 PM
From: yosi s	Respond to of 1853

eetimes.com Philips CCD rivals 35-mm quality By Peter Clarke EE Times (12/09/99, 12:07 p.m. EDT) WASHINGTON ? Digital still cameras could rival the image quality of 35-mm film photography within a couple of years due to a charge coupled device (CCD) image sensor with over six million pixels developed by Philips Semiconductors (Eindhoven, Netherlands). Herman Peek, a senior scientist at the company, presented a paper on the prototype device at this week's International Electron Devices Meeting. "This is the largest number of pixels and the smallest pixel size for a digital still camera ever published in the world," Peek said during the presentation of his paper. Although the prototype sensor is monochrome, and the use of red, green and blue filters would reduce resolution to 2 million tricolor pixels, Peek said the small size of individual light sensing elements, 3-micron x 3-micron, would allow such a sensor to rival small format film photography. "We are approaching the grain size of film, which is about 2 microns diameter, but image quality is also determined by the quality of the lens. The same thing effects CCD." Images produced using the sensor and displayed by Peek, albeit through an overhead projector system, were indistinguishable from images obtained from film. Individual hairs could been seen on the heads of head-and-shoulder portraits, which prompted congratulations from the audience. Peek said he expects to see a similar high-resolution CCD sensor in production within about two years, although it might include fewer pixels. "I don't think we will go to more pixels," he said. "We are already asking, 'Is six million too much and are we adding cost unnecessarily?' Perhaps five million or four million is the right amount." For a 2/3-inch format, Peck showed that the pixel size was on the limit of lens resolution, although the device could also be used for lens-less applications. The Philips CCD is built using a 0.5-micron CCD process operating at 14 volts and has an active area of 2,048 active lines and 3,072 active measuring 9.11 mm x 6.07 mm. The sensor has a dark current of 800 picoamperes/centimeter2 and a dynamic range of 63 dB. In his paper, Peek also discussed how novel techniques had been used to overcome problems with dark current suppression. The development of a high-resolution sensor using CCD technology represents a fight back by the technology against a challenge it faces from lower cost CMOS image sensors, which also allow the possibility of including signal processing and logic circuits on the same die. "CCD will always be expensive in comparison with CMOS image sensors," Peek said. "CCD can't compete with CMOS on price but it can on quality, and image quality is very important to consumers."