8.Features
© 2023 China Daheng Group, Inc. Beijing Image Vision Technology Branch 134
Exposure time
Readout time
All lines are exposing at the same time
All lines transfer electrons from
exposure area to storage area
Reading electrons from
storage area line by line
Time
Figure 8-12 Global Shutter
Electronic Rolling Shutter
Exposure time
Readout time
Exposure line by line
Readout after exposure
Reading
Time
Exposing
Figure 8-13 Electronic rolling shutter
The implementation process of electronic rolling shutter is as shown in Figure 8-13, different from the
global shutter, electronic rolling shutter exposures from the first line, and starts the second line exposure
after a row period. And so on, after N-1 line, the N line starts exposing. When the first line exposure ends,
it begins to read out the data, and it need a row period time to read out one line (including the line blanking
time). When the first line reads out completely, the second line just begins to read out, and so on, when
the N-1 line is read out, the N line begins to read out, until the whole image is read out completely.
The electronic rolling shutter has low price and high resolution, which is a good choice for some static
image acquisition.
The time width of the flash signal can be got by the following formula:
T
strobe
= T
exposure
–
(
N – 1
)
× T
row
Setting the exposure time
The MER-G-P/MER-G series camera supports setting the exposure time, step: 1μs. The exposure time is
shown as follows: