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C962中文资料

Description

P erkinElmer Optoelectronics, for-merly EG&G Optoelectronics, is pleased to introduce the Channel Photomultiplier (CPM), a new ultra high sensitivity optical detector which replaces conventional photo-multipliers (PMTs) and avalanche photo diodes (APDs). This device uses a unique detector principle, re-sulting in a compact design with ul-tra high gain, high dynamic range,extremely low dark current, and fast response.

T his high-performance detector offers fundamental advantages for analytical instrumentation applications such as emission spectroscopy, ?ourescence,atomic absorption spectroscopy, and bio and chemo luminescence. The CPM also delivers important advan-tages in life science products, indus-trial and medical equipment, and high-energy physics.

Principle of Operation

T he CPM, like conventional photo-multiplier tubes, converts a very low light level into photoelectrons by a semitransparent photocathode de-posited on the inner surface of the entrance window. On their way from the cathode to the anode the photo-electrons pass through a narrow, se-miconductive channel. Each time the electrons hit the inner wall of the curved channel, multiple secondary electrons are emitted. This effect oc-curs multiple times along the path,leading to an avalanche effect with a gain exceeding 108. The curved sha-pe of the glass tube improves the multiplication effect.

Features

? Ultra high anode sensitivity up to 107A/W

? Extremely low dark current, typically 3pA @ 106gain ? Very low equivalent

noise input (down to 10-17W)? Very high stability in dark current (no ”bursts”)

? High gain exceeding 108? Very high dynamic range ? Compact dimensions

? Wide spectral response through multiple window materials ? High resolution ? Fast response time

? High immunity to magnetic ?elds ?Rugged design

Cathode Channel-Entrance

Channel-End Anode

Physical Specification

C H A N N E L P H O T O M U L T I P L I E R

P R I N C I P L E O F O P E R A T I O N

C P M

W hen compared to conventional PMTs, the CPM improves anode sensitivity by one order of magni-tude, while lowering dark current by one to two orders of magnitude. The noise level shows extreme stability over time, with no ”bursts.” The extremely low dark current results in a higher dynamic range than con-ventional PMTs and extends detec-table limits for many applications.T he CPM can be used in analog-DC mode, single photon counting mode,and in nuclear spectroscopy (when coupled to scintillation materials like BGO, LSO, Nal, etc.). PerkinElmer Optoelectronics offers a choice of window materials and photocatho-des to cover the spectrum from 115 nm (UV range) to 900 nm (NIR).T he new detector is a small, head-on type with a total diameter of 10.5 mm including encapsulation. PerkinElmer Optoelectronics also offers custom con?gurations for speci?c applica-tions.

1000

1500200025003000

1 E+091 E+081 E+071 E+061 E+051 E+041 E+031 E+02

C u r r e n t A m p l i f i c a t i o n Bias Voltage (V)

Fig. 1: Typical current amplification

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1 E-051 E-061 E-071 E-081 E-091 E-101 E-111 E-12

D a r k C u r r e n t (A )

Bias Voltage (V)

Fig. 2: Typical anode dark current

C 911

C 922C 942

C 952

C 962

C 972

M A I N F E A T U R E S

Compact Size

T he CPM is one of the smallest head-on type detectors, with a 10.5 mm diameter including encapsulation. The photocathode has a useful diameter of more than 5 mm. The tube is smal-ler, easier to use, and more rugged than discrete dynode types. Only a single high voltage supply of up to 3000 volts is necessary; no external voltage divider network is required.A variety of different sizes will be avai-lable soon (1/2” and 3/4”).

Ultra high anode sensitivity A t the maximum bias voltage of 3000 V,gains can exceed 108. At 2400 V, an-ode sensitivity is typically 3 x 106A/W at a wavelength of 410 nm with a bi-alkali photocathode. This performan-ce surpasses conventional PMTs by one to two orders of magnitude and beats APDs by approximately ?ve or-ders of magnitude (Fig. 1).

Extremely low dark current T he electron multiplication in the channel is virtually silent, so dark cur-rent depends only on the photoca-thode material, leakage currents are negligible. Bialkali photocathodes ex-hibit typical dark count rates of 10cps at a gain of 3 x 108, while UV ca-thodes have dark count rates below 1cps. In analog DC mode, the typical dark noise for a bialkali photocathode is 20 pA at a gain of 107. In general,the noise level of the PerkinElmer Optoelectronics CPM is one to two orders of magnitude lower than dyn-ode PMTs, resulting in a signi?cant-

ly higher dynamic range (Fig.2).

Unpotted 1/3inch Channel Photomultiplier

PerkinElmer Optoelectronics GmbH Heimann Opto

65020 Wiesbaden, Germany PO-Box 3007

https://www.wendangku.net/doc/f31753406.html,/opto

USA

PerkinElmer Optoelectronics 2175 Mission College Blvd.Santa Clara, CA 95054Tel. ++1 (408) 565 - 0830Fax ++1 (408) 565 - 0703

https://www.wendangku.net/doc/f31753406.html,/opto

Excellent photon counting resolution

A t gains exceeding 107the single photo electron pulse is perfectly separated from the electrical noise, due to a sa-turation effect of the channel. The CPM exhibits single photon resolution with excellent peak to valley ratios.Fig. 3 shows the single photo electron spectrum taken from a multi-channel analyzer compared to a conventional photomultiplier (Fig. 3).

Choice of entrance window

T he CPM is available with different window materials,which are:

MgF 2, Quartz, UV-glass, and Borosilicate glass. The com-bination of different photocathodes and entrance windows results in a spectral range from 115 nm to 900 nm. Other window materials and photocathode combinations are available on a custom basis (Fig. 4.1 and 4.2).

Available related products

? High Voltage supply

CHV 30N (supplies 1 CPM, negative output voltage), CHV 30P (supplies 1 CPM, positive output voltage), J4-3N (supplies 10 to 15 CPMs)

? CPM Modules

MP900-series: Photoncounting module with

TTL output, including CPM, electronic and high voltage

MD900-series: DC module including high

voltage supply, ampli?er,

I/U converter, output 0 to 10 V, bandwidth 1kHz

MH900-series: High voltage module,

including CPM and

high voltage power supply ? CPM Formats

/3“ C900-series 1

/2“ C1300-series 3

/4“ C1900-series

Datasheets on request

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0C o u n t s

Channel

Fig. 3: Typical photo electron spectrum

Wavelength (nm)

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C 922

C 952

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C 972

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Q u a n t u m e f f i c e n c y (%)

100

0.1Fig. 4.1: Typical spectral response

C 973

Wavelength (nm)

100

C 942

C 943 C 962

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Q u a n t u m e f f i c e n c y (%)

Fig. 4.2: Typical spectral response

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High stability in dark current level

A s a result of the semiconductive inner surface of the CPM, no charge-up effects occur at the glass surface. This results in a very high stability of the dark current level over time, with no sudden changes (bursts). The semiconductive surface also causes high-light recovery times to be extremely small.

Technical Specifications