| Popis: |
A new generation, large frame (1317 X 1035 pel) digital camera, based on the MicroImager 1400 (MI1400), has been developed. The new MicroImager 1400-12 (MI1400- 12) uses improved noise reduction circuits to allow for 12 bit digitization up to 8 Mpel/s. Methods of correlated double sampling were investigated and a clamp-and-sample design was chosen. The MicroImager is a full frame device with a 100% fill factor. Integration time, readout frequency and pixel additive mode (binning) are under computer control. The camera outputs digital, RS-422 compatible data to the host frame memory through a 50-pin high density connector. The system is compatible with various (E)ISA and VME based imaging boards. The applications are quantitative digital microscopy in brightfield and fluorescence and in numerous industrial and medical camera applications. A number of comparative performance measurements were defined and carried out including spatial resolution (impulse response), photometric response (linearity), sensitivity, dynamic range, signal-to-noise ratio and other noise parameters. The MI1400-12 has a slightly improved impulse response. When used with primary image plane optics, the MicroImager shows a 6% improvement in the spatial resolution over standard C-mount compensation optics. In further comparisons the linearity of the MI1400-12's response holds to a coefficient of regression larger than 0.999 and has a four-fold increase in sensitivity over the MI1400. A dynamic range of 61 dB was measured for single frames corresponding to an 8 dB increase. For a 30 frame average, 77 dB was achieved. Circuit noise parameters (random noise at dark levels) improved by a factor of 3 to 4. |
