20-Mpixel CMOS image sensor: high-pixel-count imaging in small formats

September 15, 2014 // By Graham Prophet
This 20-megapixel (MP) 1.12-micron CMOS image sensor (CIS) was created for products such as high-end mobile handsets and smartphones with 1080p resolution. With an optical height of 1/2.4 inch, the T4KA7 sensor enables the development of camera modules with a z-height of 6mm or less.

The new sensor joins Toshiba's recently announced 8MP and 13MP 1.12-micron back-side illuminated CIS devices, which enable low-power, high-performance image capture and video recording. The T4KA7 employs high-speed circuit technology that delivers a frame rate of 22 frames per second (fps) at full-resolution image capture – an improvement of 83% compared to Toshiba’s previous 20MP sensor.

Drivers of this image sensing sector, according to analysts, include not only mobile technologies (as the industry shifts further toward use of CMOS in place of CCD image sensors), but also automotive, industrial and medical imaging applications, as well as wearable electronics.

The T4KA7 has a pixel count of 5384 (H) x 3752 (V). The 20MP back-side illuminated sensor’s advanced digital zoom capability delivers virtually no discernible image deterioration, even when zooming in very close on the subject being photographed with an advanced tablet or smartphone. Other features include auto-defect pixel correction and 16 kbit one-time programmable (OTP) memory, enabling tight integration of high-density permanent memory without increasing the real estate on the sensor chip.

Other sensors in the series are the 13MP T4K82 that enables 240 fps HD video capture for higher-end mobile devices with 1080p resolution; and the 8MP T4KA3 which targets midrange smartphones, tablets and action cameras with 720p resolution, enabling HD video capture at 240 equivalent frames per second (fps). Both sensors feature Bright Mode and High Dynamic Range (HDR) technology.

Toshiba; www.toshiba-components.com