The ICX638AKA and ICX639AKA are products mainly designed for security camera application and are diagonal 6.0 mm (Type 1/3) 380K/440K-pixel color CCDs. These products provide improved characteristics compared to the existing ICX408AK and ICX409AK. These new devices provide significant improvements in the sensitivity characteristics, which are critical for security camera applications, while maintaining the same saturation signal level and smear level characteristics as the existing products.
The ICX638AKA and ICX639AKA of this release provide a significantly improved focusing of light onto the photodiodes due to an increased aperture ratio and an improved upper section structure.
This suppresses the reduction in collection ratio due to the increased angles of incident light rays that occurs when the lens is used at its widest aperture. Also, by adopting new complementary color pigments in the color filters, Sony increased the sensitivity to the blue end of the spectrum (shorter wavelengths) and achieved well-balanced spectral sensitivity characteristics. (See figure 1.)
The combination of these technological improvements results in a significant increase in the sensitivity characteristics that totals +7 dB. When one compares actual images, one can clearly see that the image quality under the low-light conditions that are critical for security camera applications has been improved significantly.
