CN2476876Y

CN2476876Y - Hard x-ray cathode image intensifier

Info

Publication number: CN2476876Y
Application number: CN 01212968
Authority: CN
Inventors: 赵宝升; 赵养社
Original assignee: XiAn Institute of Optics and Precision Mechanics of CAS
Current assignee: XiAn Institute of Optics and Precision Mechanics of CAS
Priority date: 2001-01-21
Filing date: 2001-01-21
Publication date: 2002-02-13
Anticipated expiration: 2011-01-21

Abstract

The utility model relates to a hard X-ray cathode image intensifying device which is used in medical treatment, industrial nondestructive inspection and safety inspection. The utility model has a vacuum tube crust that is formed by a titanium sheet input window and a screen output window and a micro passage board whose input surface is vapor deposited with X ray cathode material layer. The X ray cathode material layer is a layer of alkali and halogen compound of a thickness of 0.2 to 0.5 mm and the relative density is larger then 80 percent. The product has the characteristics of high output illumination, small flicker noise and high space distinguishability.

Description

Hard X ray negative electrode image intensifier

The utility model belongs to the x-ray Instrument technology field, relates to a kind of hard X-ray image intensifier, and its product can be suitable for using in the x-ray instrument of aspects such as medical treatment, industrial nondestructive testing and safety inspection.

Present X ray image intensifier than advanced version well known in the art, as in the ZL89221880.0 patent text, addressing the X ray image intensifier, because the cathode construction that is adopted is the CsI material of a kind of loose uniform density (relative density is 5%), need during its evaporation to fill argon gas about 10 holders to vacuum coating equipment, it is low to exist output brightness comparatively speaking, flicker noise reaches the low problem of spatial resolution greatly, thereby its product only can be applicable to the X ray detection [draw from J.E.Bateman " Advances in Electronicsand Electron Physics, Vol.52 (1979) "] of energy less than 10Kev.

The purpose of this utility model is to overcome the existing in prior technology deficiency, so provide a kind of rational in infrastructure, volume is little and hard X ray negative electrode image intensifier with higher output brightness and high-resolution.

Foregoing invention purpose of the present utility model is achieved by the special ZL89221880.0 technical pattern of prior art is made improvements, its architecture advances scheme is such: the microchannel plate (MCP) that is provided with evaporation X ray cathode material layer on the input face in a vacuum envelope with the thin input window of titanium and phosphor screen output window, post fluorescence coating at phosphor screen output window inner surface, be provided with lead glass outside output window, said X ray cathode material layer is that thickness is 80～100% alkali halogen compound material layer in 0.2～0.5mm and relative density.In the course of work, behind excitation of X-rays X ray cathode material, produce a large amount of once, secondary electron directly enters the passage of MCP, electronics is in the passage multiplication of MCP, its gain can reach 103～104 times, and these electronics emit from the output face of MCP, after electric field quickens, directly the impact fluorescence screen makes the phosphor screen luminescence imaging.

Below with reference to accompanying drawing behind the literary composition the utility model content is described further.This accompanying drawing is the structural principle schematic diagram of an embodiment of the utility model.

Referring to accompanying drawing, hard X ray negative electrode image intensifier described in the utility model mainly is made up of input titanium window 1, X ray negative electrode 2, microchannel plate 3, fluorescence coating 4, phosphor screen output window 5, lead glass 6, tile type power supply 9 and ABS engineering plastics shell 8 etc.Parts 1～5 constitute vacuum tube, X ray negative electrode 2 wherein is a kind ofly can directly X ray be changed into photoelectronic photoemissive material by what the close alkali halogen compound material (as CsI, KCl, KBr etc.) of unusual matter constituted, its method by vacuum evaporation is securely on the input face attached to microchannel plate 3, evaporation thickness is 0.2～0.5mm, and relative density is 80～100%.The lead glass of a 6～8mm is installed before phosphor screen output window 5; be used to protect the observer not to be subjected to radiohazard; outside vacuum envelope, be provided with shell 8 by ABS engineering plastics injection-compression molding; with silicone rubber insulation layer 7 embeddings, be exposed in the air in the middle of the shell 8 so that the electrode of the electronic device of all power supplys and image intensifier is unlikely.

Compared with prior art, the advantage that has of the utility model is:

One, the X ray negative electrode that adopts the unusual close alkali halogen compound material of matter to make, has higher absorption emission ratio for energy at the X ray of 40～100Kev, it effectively makes the output area at Φ 50～120m, and its image output brightness is at 40cd/m²More than, spatial resolution is greater than 41p/mm, and flicker is made an uproar Statement is aobvious to diminish, and picture contrast obviously improves.

Two, adopting titanium thin as input window, because titanium density is less relatively, improved the transmitance of X ray greatly, because titanium has mechanical preferably ductility, is again a kind of vacuum sealing material preferably therefore again.

Three, adopt miniature tile type power supply as the image intensifier working power, only need input 12V DC power supply, micro power offers image intensifier required voltages at different levels by inversion, multiplication of voltage, feedback circuit, makes its operate as normal.

Four, adopt the shell of ABS engineering plastics injection-compression molding, good looking appearance is generous, compact conformation, and booster inside is with epoxy sealing, good insulation preformance.

Claims

1, a kind of hard X ray negative electrode image intensifier, it is characterized in that in a vacuum envelope with the thin input window (1) of titanium and phosphor screen output window (5), being provided with the microchannel plate (3) of evaporation X ray cathode material layer (2) on the input face, post fluorescence coating (4) at phosphor screen output window (5) inner surface, be provided with lead glass (6) outside output window (5), said X ray cathode material layer (2) is 80～100% alkali halogen compound material layer in 0.2～0.5mm and relative density for thickness.

2, hard X ray negative electrode image intensifier as claimed in claim 1 is characterized in that said X ray cathode material layer (2) made by the CsI material.

3, hard X ray negative electrode image intensifier as claimed in claim 1 is characterized in that adopting miniature tile type power supply (9) as the image intensifier working power.

4, hard X ray negative electrode image intensifier as claimed in claim 1 is characterized in that said vacuum ray field work shell places a shell by ABS engineering plastics injection-compression molding (8).