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Because of ov(onmiversion) can't garantee any aperture 2.8 lens with their sensor - ov5640 can pass the windows hardware certitication kit - Webcam Snesor Quality System Test, I try to tuning the iq by myself.
Below list are the solutions I try to tuning iq of. Although the aperture 2.8 is not good enough,
I think the module house don't must to be using the lens with the 2.4 or beter aperture in order to pass the WHCK item - Webcam Sensor Quality System Test.
Solution1 - ov5640(Omniversion,sensor vender)+rts5821z(Realtek,dsp vender)+gs8657bb(GSEO,lens vender)(fixed focus)
Solution2 - ov5640(Omniversion,sensor vender)+rts5830VB(Realtek,dsp vender)+.L9467A5(Largen,lens vender) with vcm (auto focus)
All the iq engineer must attent the digital multi alalog gain before gain night threshold of ov5640 is not good enough, so the 80lux 30fps limitation may not arrive.
People should use other digital process to pass the frame rate limitation of normal light.
Another important thing is people need to know the item of mtf30/snr is inferenced by vcm(voice coil motor) auto focus.
Before the vcm working in win8.1 iq tset is finished, the focus process must to be affected by Gravitation,
so the focal plane of lens is not parallel with the win8.1 test chart plane. The normal vcm just move the x-y paln to focus the target,
if someone need consider the influence of gravitation, you can consider the beter and complex vcm can control the z dirction to avoid problem of tilt.
Video displayed
But, about this solution 1 report, there are two small item are failed - VFOV and inter-frame time.
( Don't consider the upside 1/2 resign is another front camera result and the applying filter 2728 is filter all the fail of "Webcam Sensor Quality System Test")
Because the whck result doen't match with the the specification Microsoft release. The VFOV failed is a issue.
It need Microsoft to clear this bind spot.I had sent the mail to require it. It may take a long time to receive more message.
The inter-frame time issue is consider to the frame rate and hardware performance.
The iq engineer just only can promise the customer the frame rate is high enough to pass the criteria at the environment of 80lux and 20lux.
If the hardware/river performance is not good enough, the jitter and inter-frame time still maybe fail.
Btw, if we disable and uninstall the front camera, we can just test another camera(rare camera),
the report formt is a little different from the above report. Maybe someone is interested in this. I also arange the data from the log file into excel.
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