Bezryadin. Digital Still Camera Detector System Quality Criterion. The most widely used detector type.

5. The most widely used detector type.

Let us consider the deviation from FCS for DSS of one of the typical CCD matrix ICX284AQ (Sony). The DSSs of its sensors are displayed in Fig.5.1 with bold solid lines. Residual DSS components are displayed with dotted lines.

Fig.5.1. The ICX284AQ DSSs are displayed with bold solid lines. Residual DSS components are displayed with dotted lines.

The usage of traditional UV+IR extra filter (solid black line) significantly improves the situation near the boundaries of the visual range.

Fig.5.2. The ICX284AQ with UV+IR extra filter DSSs are displayed with bold solid lines. Black line represents filter. Residual ICX284AQ+filter components are displayed with dotted lines. Thin lines represent the original ICX284AQ DSSs

However, the residual components of ICX284AQ+filter are still large in the middle of the range. They might be reduced with an extra filter with a complicated configuration, like the one shown in Fig. 5.3 with the black line:

Fig.5.3. Thin solid lines represent the original ICX284AQ DSSs, bold solid lines represent ICX284AQ+filter DSSs, and residual ICX284AQ+filter components are displayed with dotted lines. Black line represents filter

The ICX284AQ DSS deviation from FCS, defined with 10° CIE standard are in the table below.

Sony ICX284AQ	r	g	b	MRS
No Filter	42°	12°	25°	29°
Traditional Filter	20°	5°	23°	18°
Modern Filter	18°	7°	8°	12°

Tab. 5.1. The ICX284AQ DSS deviation from FCS, defined with 10° CIE standard.

As it might be seen from the table, the deviation is still beyond the acceptable 5° accuracy. The main cause for it is an inappropriate choice of red detector. The maximum of red detector SS have to be shifted to the left and the left hand of the curve have to be more gently sloping. This defect cannot be corrected with an extra filter.

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