Toshiba is a leader in advanced CMOS image sensor technology. The Toshiba CMOS image sensors employ a low-noise pixel structure that achieves high-picture quality with low-power consumption, even in low-light conditions for camera phones and other mobile applications. The latest technologies now available from Toshiba include High Dynamic Range (HDR) for more detail in dark and light areas; Color Noise Reduction (CNR) for truer colors; backside illumination (BSI) for better image quality even in low-light conditions.

• Better image quality
• More detail in dark and light areas
• Truer colors with a wider range of intensity

Non-HDR cameras take pictures at one exposure level with limited contrast range, which results in the loss of detail in the bright or dark areas of a picture, depending on the setting of the camera. HDR compensates for this loss of detail by taking multiple pictures at different exposure levels and intelligently stitching them together to produce a picture that is representative in both dark and bright area.

The Toshiba image sensors employ an alternate-row, dual exposure HDR technology, which not only significantly improves dynamic range, but also reduces motion artifacts and eliminates frame buffer requirement without compromising frame resolution or speed. The Toshiba HDR solution offers a powerful tool for various scene options and optimal user experience.

• Improves signal to noise ratio
• Better image quality
• Truer colors

As pixel size decreases due to miniaturization in today's image sensors light sensitivity has decreased resulting in signal noise, which appears as color speckles reducing image quality. However, when integrating a color noise reduction (CNR) filter with backside illumination (BSI) technology optimum image quality results. For example, the Toshiba T4K37 CMOS image sensor with a 1.12 micrometer pixel and CNR provides approximately 1.5* times higher signal to noise ratio (SNR ) value than a 1.12 micrometer pixel image sensor without CNR and also provides an SNR value equivalent to a 1.4 micrometer pixel image sensor without CNR.

*Based upon Toshiba measurements

• Better light absorption
• Increased light sensitivity
• Combined with CNR for optimum image quality

As pixel sizes shrink there is a reduction in the amount of light available to be captured by the photodiodes. BSI solves this problem by deploying lenses on the silicon substrate behind the sensor and not on the front where wiring interferes with light absorption. "Backside" positioning boosts light sensitivity and absorption by 40% compared to conventional technologies, and allows formation of finer image pixels. Toshiba has made full use of the advantages of BSI to realize image pixels with a pitch of 1.12 microns, and to pack 13.1 million of them into a 1/3.07-inch optical format sensor that meets high level imaging and processing requirements. Toshiba will continue to offer image sensors with smaller and smaller pixel sizes that utilize BSI technology bringing a new level of quality and smaller form factor to mobile phone applications.

The new Toshiba TCM9930MD image sensor using flip-chip packaging fits into the industry's thinnest low-profile camera module measuring only 4.7 mm in height. Flip-chip packaging allows for a large number of interconnects with shorter distances than wire to greatly reduce the assembling area and package height.

Flip-chip packaging is a method of electrically connecting the die to the package carrier. Instead of using a wire for this connection, a conductive bump placed on the die surface is used. The die is then flipped over and placed face down with the bumps, typically 60 to 100 um high, connecting directly to the carrier. Flip-Chip technology not only reduces packaging height, but it reduces signal inductance, power/ground inductance and provides higher signal density.