Phosphor Screens


The phosphor screens used by the BVS and BIS systems are available separately. These screens have the same outer diameter as standard 18mm or 40mm microchannel plates (MCP). Custom screens are also available.  The standard screens consist of a glass disc or fiberoptic plate uniformly coated with P-20 phosphor and are aluminized. An extra layer of aluminum is deposited in a ring 0.050" (1.27 mm) wide on the outer diameter of the phosphor screens. This allows for electrical contact to the phosphor screen using optionally available metal contact rings. Screens are aluminized to increase light efficiency by up to 100% since light created at the phosphor is reflected back at the aluminum layer. Also, the conductive aluminum layer aids in the reduction of charge build up from electrons and ions. If the phosphor screen is used in conjunction with an electron multiplier such as a MCP, an electron acceleration energy of 3kV will be required to pierce the aluminum layer. If this acceleration voltage is too high for a particular application, indium-tin-oxide (ITO) coated screens can be used to provide the conductive base needed to minimize the electrostatic effects of charged particles. Phosphor screens can also be ordered with any of the phosphors shown in table 2.  below  and ultra fine particle phosphors in the 1-2 micron range are available for high resolution x-ray imaging. Electron microscope photographs of the phosphor screens have shown a compact (15mg/cm2),  uniform coating that varies only within the grain size of the phosphors.  The thickness of custom screens can vary from 2-4 microns for high resolution purposes, to several hundred microns for x-ray purposes. If a custom size is required, or you need your own disc re-coated, please fill out the form at the bottom of the page for a quotation.

 

TABLE 1. STANDARD COLUTRON PHOSPHOR SCREENS

Part Number

Material

Phosphor Type

Phosphor Thickness

Dimensions f (mm diameter)

Effective Area f (mm diameter)

Thickness (mm)

Tapered Ratio

Input Surface

Output Surface

Input Surface

Output Surface

805-1

Glass disc

P20 Aluminized

P20: 10-15 m Al: 250-500

24.76

24.76

22.22

22.22

1.55

1:1

805-2

Glass disc

P20 Aluminized

P20: 10-15 m, Al: 250-500

50.17

50.17

47.63

47.63

1.55

1:1

705-1

Fiberoptic

P20 Aluminized

P20: 10-15 m, Al: 250-500

22.23

22.23

19.69

19.69

6.36

1:1

705-2

Fiberoptic

P20 Aluminized

P20: 10-15 m, Al: 250-500

28.14

13.7

25.60

12.80

28.0

2:1

705-3

Fiberoptic

P20 Aluminized

P20: 10-15 m, Al: 250-500

41.0

13.7

38.46

12.82

41.0

3:1

705-4

Fiberoptic

P20 Aluminized

P20: 10-15 m, Al: 250-500

54.8

13.7

52.26

13.07

60.0

4:1

 

TABLE 2. PHOSPHOR TYPES AND CHARACTERISTICS

Phosphor Type*

 

Chemical Composition

Typical Peak Wavelength

Fluorescent Color

Chromaticity Coordinates

       (X,Y)

Decay Time

Typical Quantum Yield (photons/electron-volt)

Typical Absolute Efficiency (radiated watts/watt excitation

Remarks

EIA WDTS

  P1

GJ

Zn2SiO4:Mn2+ 525 nm Yellowish- green 0.218, 0.712 1-100ms - - Used in Oscilloscopes, radar

P11

BE

ZnS:Ag

460 nm

Blue

0.139, 0.148

34m s

0.038

0.10

Good energy conversion (efficiency) for blue light

P15 GG ZnO:Zn 504 nm Green 0.246, 0.439 1-10m s - -

Used in Flying-spot equipment, photography

P20

KA

(Zn,Cd)S:Ag

560nm

Yellow-green

0.426, 0.546

60m s

0.063

0.14

Good energy conversion (efficiency)for green light, Good for UV radiation, 250nm to 300nm

P22 R XX Y2O2S:Eu3+ - Reddish-orange 0.639, 0.353 1-100ms     Used in color TV
P22 G XX ZnS:Cu, Al - Yellowish-green 0.281, 0.621 1-100ms     Used in color TV
P22 B XX ZnS:Ag - Blue 0.147, 0.152 1-100ms     Used in color TV
P24 GE ZnO:Zn 510 nm Green 0.238, 0.417 1-10m s     Flying-spot equipment
P31 GH ZnS:Cu 520 nm Green 0.296, 0.577 10m s- 1ms     Used in Oscilloscopes

P43

GY

Gd2O2S:Tb3+

545 nm

Green

0.344, 0.568

1ms

-

-

Excellent scintillator for x-rays < 250nm.

Emission efficiency: 13%

Absorption characteristics:

K-edge, 50.22 keV 

Effective atomic # 59.5

P45

WB

Y2O2S:Tb3+

-

White

0.251, 0.304

1-100ms

-

-

Used in displays

P46

KG

Y3Al5O12:Ce3+

530nm

Yellow-green

0.294, 0.532

300ns

-

-

Flying-spot equipment

P47

BH

Y2SiO5:Ce3+

400nm

Violet-blue

0.173, 0.088

55ns

-

-

 Fast Decay Photography

P48

KH

Y3Al5O12:Ce3+(70%) Y2SiO5:Ce3+(30%)

- Yellow-green

0.392, 0.507

-

-

-

Flying-spot equipment

P53

KJ

Y3Al5O12:Tb3+ 544 nm Yellowish-green 0.392, 0.507 1-100ms

-

-

Head-up displays

* EIA- Electronics Industries Association of the USA. These symbols have been in use since 1945.

   WTDS- Worldwide Phosphor Type Declaration System. Established in 1982.

REQUEST FOR  QUOTATION FORM (CUSTOM PHOSPHOR SCREENS)

 PHOSPHOR TYPE      CONDUCTIVE COATING    SUBSTRATE DIMENSIONS &TYPE

P-11                ITO (Indium-Tin-Oxide)        (Glass)

P-20                Al (Aluminum)                          Dimensions

P-43                None                                  (Fiberoptic)

P-46                                                                  Dimensions

P-47

Other (See Phosphor list in above table):

Phosphor thickness (microns):

 

Quantity:

 

Name: Company/Institution:

Address: Country:

Email Address:

Phone:

Fax:

 

Please enter other special requests or comments below.

 

 

 

 


Home Beam Imaging Systems-BIS Beam Viewing Systems-BVS Power Supply Control Units-PCU

Image Processing Systems-IPS