Chapter 1 Introduction; Photonmax™ Cameras; Emccd Technology And On-Chip Multiplication Gain - Princeton Instruments PhotonMAX System Manual

Introduction
Thank you for purchasing a PhotonMAX camera system from Princeton Instruments/
Acton. Your system has been thoroughly tested to meet the exacting standards of
PI/Acton and to meet the demanding requirements of many low light level imaging
applications.
Please read the manual carefully before operating the camera. This will help you optimize
the many features of this camera to suit your research needs.
PhotonMAX™ Cameras
The new PhotonMAX™ cameras feature on-chip
multiplication gain, a technology that enables the
multiplication of photon generated charge right on the CCD.
This approach offers an effective alternative to traditional
ICCD cameras for many nongated, low-light applications.
The PhotonMAX:512B, the first in the series, features
square, 16 x 16 µm pixels in a 512 x 512, frame-transfer
format. The back-illuminated CCD with dual amplifiers ensures optimal performance not
only for applications that demand the highest available sensitivity but also for those
requiring a combination of high quantum efficiency and wide dynamic range. Deep
thermoelectric cooling and state-of-the-art electronics are employed to help suppress
system noise. The camera can be operated at 10 MHz for high-speed image visualization
or more slowly for high-precision photometry. Supravideo frame rates are achievable via
subregion readout.

EMCCD Technology and On-Chip Multiplication Gain

The principal difference between an electron-multiplying CCD (EMCCD) and a traditional
CCD is the presence of an extended serial register in the new device (see Figure 1). Electrons
are accelerated from pixel to pixel in the extended portion of the serial register (also referred
to as a multiplication register) by applying higher-than-typical CCD clock voltages. This
causes secondary electrons to be generated in the silicon by impact ionization. The degree of
multiplication gain is controlled by increasing or decreasing the clock voltages for this
register (gain is exponentially proportional to the voltage). Although the probability of
generating secondary electrons is fairly low (typically 0.01 per stage), over the large number
of stages of a typical multiplication register, the total gain can be quite high.
This technology combines the ease of use and robustness of a traditional CCD with the
gain capabilities of an intensified CCD in a single device. The combination of this
technology with frame-transfer readout makes the PhotonMAX cameras excellent
choices for experiments where fast framing and low light sensitivity are required.
Chapter 1
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