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AD111 Photobyte-P Detector

AD111 Photobyte-P: Photo-Multiplier Detection System


- Provides a complete detection system for SP's Digikröm monochromators.
- Easy USB 2.0 interface.
- Wide selection of PMTs.


The AD111 is a convenient computer controlled photomultiplier detection system for use with Spectral Products’ Digikröm line of monochromators. It features a detector housing that has a dynode divider chain and direct anode connection, mounts directly to exit-slit ports of Digikrom monochromators, and accommodates side-on photomultiplier tubes. (PMT’s must be ordered separately.) It also features the Photomultiplier Amplifier, a compact electronic unit containing the preamplifier and high voltage power supply for the PMT. Coaxial cables for the high voltage and PMT output current signals connect between the detector housing and the amplifier unit. The entire operation, including wavelength and bandpass selection, is controlled with a customer-supplied PC. (The Digikrom monochromator and the AD111 utilize one serial for monochromator and one USB port for AD111) An easy to use program is also included that allows full control of both PMT and monochromator. It graphically displays wavelength versus intensity, intensity versus time and allows ASCII data storage for importing to other user interfaces as desired.




Wavelength Range Per PMT detector (see below)
High Voltage Range 0 - 1000V DC
A/D Resolution 16-bit (Successive Approximation)
Response Rate USB 2.0
High Voltage Resolution 244mV
Input Voltage ± 5V DC
Data Resolution 76.3mV (data range = 0 - 5V)
Time Constant per step Selectable from 1ms to 10s
Conversion Time 2ms (max.)
USB 2.0 Transfer Rate 480MB/s
Amplification Gains x1 to x10 (programmable)
Supply Voltage 100 - 240V AC
Current Input Range

0 to -5m A


Spectral Products offers the following PMTs for use with the AD110.


AP Part # Code

PMT Type

Wavelength Range and Spectral Response

AD311 Per PMT detector (see below) 185 - 900nm; S-20 (extended)
AD321 0 - 1000V DC 185 - 650nm; S-5
AD322 16-bit (Successive Approximation) 400 - 1100nm; S-1
AD323 USB 2.0 185 - 850nm; S-20
AD324 244mV 185 - 930nm; GaAs (extended)


Other PMTs are available from SP by request.