In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Tracy Allen wrote:

Hi George,

I settled on the Microsemi light sensors, specifically the LX1973A, for a similar application.  It is a photometric response (peaked in yellow to follow the human eye response), meant for control of backlighting in such things as computers and automobile dashboards.   It is not meant as a scientific instrument, but with a little calibration it is quite good and much easier to use than the Taos sensor.      The output is a single analog current (or voltage) that covers 5 or 6 decades of light level.   The curve is compressed to the fourth root of light intensity (in order to get the dynamic range), but with only one variable it is much easier to implement the math and the calibration.

I'm using this sensor at very low light levels, as it is good down to levels of 0.01 lux or even 0.001 lux for night or moonlight, and its natural full scale only goes up to about 100 to 500 lux (bright indoor room light level).   But that can be scaled with a neutral filter, or a color shaping attenuation filter if you want.

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