For spectroscopy experiments in the ultraviolet-visible–near infrared region of the spectrum, a Photomultiplier tube (PMT) is perfect for the detection of light. Standard PMTs can be used from 185 to 900 nanometers; special PMTs can expend this wavelength range.

A PMT is extremely sensitive, allowing the measurement of very low levels of light. It has a wide dynamic range, so it can also measure high levels of light. It is very fast; so rapid spectral events can be reliably monitored. As a practical matter, PMTs are durable, long-lived, and economical. And with OBB’s Photomultiplier Detection System, it is very convenient and easy to use.

The Photomultiplier Detection System 3000 from OBB Corp is built as complete system using modern design techniques and components. You won’t find anything like them elsewhere. Everything needed to measure the intensity of the light is packaged in a compact, attractive housing that attaches conveniently to your experiment. There are no unsightly boxes for power supplies or a multitude of cables tangled on your bench-top.

The system incorporates a high voltage supply, detector electronics, and the controls in a compact, attractive housing that also contains the PMT. You have a choice of standard PMTs to choose from, the reason why they are not included with your system. The PMT high voltage is shown on a digital display on the housing or you can select to show the actual analog signal from the PMT with just a flip of a switch. The high voltage can be adjusting manually or controlled externally with a signal at the “External Voltage Control” BNC. Power is delivered from an external supply that is included. Computer interface and Microsoft compatible software complete the package.

 

• Compact Size —H 7.25 in. (18.3 cm) x  W 3.75 in. (9.5 cm) x D 3.75 in. (9.5 cm.)
• Inexpensive—We make so many that the price is very low
• Complete Package—Everything is included even the software
• Wide Choice of PMTs—Will accommodate virtually any 1 1/8 in. diameter side-on PMT tubes
• Easily Compatible—Will easily mount to fit your detection needs

 

OBB’s PMT housing will accept a wide variety of side-on 1 1/8-inch diameter photomultiplier tubes. It is optimized for PMTs with uniform dynode chains. PMTs are normally selected based on their wavelength response and their noise and/or sensitivity characteristics. OBB offers four different PMTs, as standard, for use with our PMT housing. We can and do offer special PMTs for custom applications.

Specifications
Spectral Response	185 to 650 nm	185 to 900 nm	185 to 680 nm	185 to 810 nm
Wavelength of Maximum Response	340 nm	400 nm	400 nm	350 nm
Cathode Sensitivity Luminous Radiant at 400 nm	40 µA/lm 48 mA/W	250 µA/lm 74mA/W	60 µA/lm 60 mA/W	45 µA/lm 40 mA/W at 350 nm
Anode Sensitivity (at 1000 V) Luminous Radiant at 400 nm	400 A/lm 4.8 x 105 A/W	2500 A/lm 7.4 x 105 A/W	400 A/lm 4.0 x 105 A/W	100 A/lm 9x104 A/W at 350 nm
Gain	1 x 107	1 x 107		2.2 x 106
Low Dark Current	5 nA	3 nA	0.1 nA	2 nA

 

Data Acquisition Specifications:

Data Rate: 1 point/100 sec to 500,000 points/sec

All units have line voltage power supply, power on/off switch, high voltage adjustment, LCD high voltage display, signal output BNC connection, external high voltage adjust input BNC connection, RF shielded case, output mode control, and socket for most 1 1/8-inch side-on photomultiplier tubes, I/O board and software.

High Voltage Power Supply Specifications
Input	± 15 VDC, 250 mA
High Voltage	-200 to -1,100 VDC manually adjustable LCD displays actual cathode voltage
External High	0 to +5 VDC (0 = -200 V, 5 = -1,100 V)
Voltage Adjust	Continuously adjustable
Input Regulation	± 0.05% max. (for 15 V ± 1 V input).
Load Regulation	± 0.05% max.
Ripple	100 mV p-p max.
Temperature Coefficient	± 0.01% max. (+5 to 40°C)
Drift	± 0.03%/hr. max. (after 15 minute warm-up)

 

Line Voltage Power Supply Specifications
Input	115 or 220 VCA (specify at time of order)
Output	±15 VDC, 250 mA

 

Analog Unit Specifications
Gain Settings:	1 µA = 1 V 0.1 µA = 1 V 0.01 µA = 1 V 0.001 µA = 1 V
Time Constant Settings:	0.05 msec 0.5 msec 5 msec 50 msec 500 msec (0.5 sec)
Offset Correction:	± 50 nA
Dimensions, in (mm):	H 7.25 (183) x W 3.75 (95) x D 3.75 (95)
Weight, kg (lb):	0.997 (2.2)