ALLIED Vision Technologies Guppy F-503 - Manual (Page 154)

Description of the data path
GUPPY Technical Manual V7.1.0
154
HDR (high dynamic range) (GUPPY F-036 only)
The HDR mode is available for the GUPPY F-036 cameras with the Micron/
Aptina MT9V022 sensor. (HDR = high dynamic range)
HDR enhances the range of illumination levels that can be distinguished. The
MT9V022 sensor gives you an intrascene optical dynamic range exceeding
110 dB.
Thus the GUPPY F-036 cameras are ideal for interior and exterior automo-
tive, security and machine-vision imaging.
HDR overview (HiDy sensor)
With the MT9V022 sensor you achieve a high, intrascene-dynamic range the
so-called HiDy. This is Micron/Aptina’s name for the HDR mode.
Analog signal chain and ADC are designed in a manner that saturation occurs
only at extremely high levels of illumination. The pixel operation allows
automatic exposure control of the pixel saturation level and manual adjust-
ment of the knee points (one or two) during the exposure period. The auto-
matic control creates a piece-wise linear response to the illumination. Expo-
sure time is controlled automatically, whereas you adjust manually the max-
imum storage charge of the pixel knee points to get a response curve that is
a combination of piece-wise linear segments of decreasing gradients.
Figure 91: HDR response curves
Knee points
Piece-wise linear response
Linear response
Saturation
Input illumination
AD
C output