Digital radiography panel with pressure-sensitive adhesive for optical coupling between scintillator screen and detector and method of manufacture
View Patent ↗A digital radiography panel has a scintillator screen having a light-exiting surface from a material with a first index of refraction n 1 and a photosensor array having a light-accepting surface from a material with a second index of refraction n 2 . A pressure-sensitive adhesive couples the light-exiting surface of the scintillator screen to the light-accepting surface of the photosensor array and has a third index of refraction that has a value n PSA that either lies in the range between n 1 and n 2 , or substantially matches n 1 or n 2 , or both.
1. A digital radiography panel comprising:
a scintillator screen having a light-exiting surface from a material with a first index of refraction n 1 ;
a photosensor array having a light-accepting surface from a material with a second index of refraction n 2 ; and
a dry form pressure-sensitive adhesive to adhere to opposing dissimilar surfaces without further activation to bond the light-exiting layer of the scintillator screen to the light-accepting layer of the photosensor array and having a third index of refraction that has a value n PSA that either lies in the range between n 1 and n 2 , or substantially matches n 1 or n 2 , or both.
2. The digital radiography panel of claim 1 wherein index of refraction n PSA further substantially meets the following condition:
n PSA =√{square root over ( n 1 n 2 )}.
3. The digital radiography panel of claim 1 wherein index of refraction n PSA further meets the following condition:
|( n 1 −n PSA )|≦0.12 or |( n PSA −n 2 )|≦0.12.
4. The digital radiography panel of claim 1 wherein index of refraction n PSA further meets the following condition:
|( n 1 −n PSA )|≦0.08 or |( n PSA −n 2 )|≦0.08.
5. The digital radiography panel of claim 1 wherein index of refraction n PSA further meets the following condition:
|( n 1 −n PSA )|≦0.04 or |( n PSA −n 2 )|≦0.04.
6. The digital radiography panel of claim 1 wherein the light-exiting surface is on a coating deposited over a scintillator material.
7. The digital radiography panel of claim 1 wherein the pressure-sensitive adhesive comprises a cross-linked polymer.
8. The digital radiography panel of claim 1 wherein the pressure-sensitive adhesive is releasable.
9. The digital radiography panel of claim 8 wherein the scintillator screen is a first scintillator screen, wherein the releasable dry-form pressure-sensitive adhesive is configured to replace the first scintillator screen from the releasable dry-form pressure-sensitive adhesive by removing the first scintillator screen to apply a second scintillator screen onto the releasable dry-form pressure-sensitive adhesive, wherein the second scintillator screen is for a different type of radiographic image than the first scintillator screen.
10. The digital radiography panel of claim 1 wherein the light-accepting surface is on a passivation layer.
11. The digital radiography panel of claim 1 wherein the scintillator screen is formed on a flexible substrate.
12. The digital radiography panel of claim 1 , wherein the scintillator screen has an index of refraction n 0 , a protective layer coupled to the scintillator screen having the light-exiting surface from the material with the first index of refraction n 1 , wherein the index of refractions satisfy n 0 is less than n 1 , n 1 is less than n PSA , n PSA is less than n 2 .
13. The digital radiography panel of claim 12 wherein index of refraction n PSA further substantially meets the following condition:
n PSA =√{square root over ( n 1 n 2 )}.
14. A method of fabricating a digital radiography panel, comprising:
providing a scintillator screen having a light-exiting surface from a material with a first index of refraction n 1 ;
providing a photosensor array having a light-accepting surface from a material with a second index of refraction n 2 ; and
applying a pressure-sensitive adhesive between the light-exiting surface and the light-accepting surface, wherein the scintillator screen is a first material scintillator screen including characterisitics for a first type of radiographic image and further comprising
peeling the first material scintillator screen from the pressure-sensitive adhesive to remove the first material scintillator screen; and
applying a second material scintillator screen onto the pressure-sensitive adhesive, wherein the second material scintillator screen includes characterisitics for a second different type of radiographic image than the first material scintillator screen.
15. The method of claim 14 wherein applying the pressure-sensitive adhesive comprises:
peeling off one or more release layers from the pressure-sensitive adhesive for bonding the screen to the array; and
pressing and rolling a roller over the combined screen, pressure-sensitive adhesive and array.
16. The method of claim 14 wherein applying the pressure-sensitive adhesive comprises:
peeling off one or more release layers from the pressure-sensitive adhesive for bonding the screen to the array; and
feeding the combined screen, pressure-sensitive adhesive, and array between heated rollers.
17. The method of claim 14 wherein the scintillator screen has an index of refraction n 1 , a protective layer coupled to the scintillator screen includes the light-exiting surface from the material with the first index of refraction n 1 , the pressure sensitive adhesive has an index of refraction n PSA , wherein the index of refractions satisfy n 0 is less than n 1 , n 1 is less than n PSA , n PSA is less than n 2 .
18. A method of fabricating a digital radiography panel, comprising steps of:
providing a scintillator screen having a light-exiting surface from a material with a first index of refraction n 1 ;
providing a photosensor array having a light-accepting surface from a material with a second index of refraction n 2 ; and
applying a dry-form sheet pressure-sensitive adhesive between the light-exiting surface and the light-accepting surface after respectively removing a first release layer and a second release layer from opposite sides of the dry-form sheet pressure-sensitive adhesive.
19. The method of claim 18 wherein applying the dry-form sheet pressure-sensitive adhesive comprises:
peeling off one or more release layers from the pressure-sensitive adhesive for bonding the screen to the array; and
pressing and rolling a roller over the combined screen, pressure-sensitive adhesive and array.
20. The method of claim 18 wherein index of refraction n PSA of the dry-form sheet pressure-sensitive adhesive substantially meets the following condition:
n PSA =√{square root over ( n 1 n 2 )}.
21. The method of claim 18 wherein the screen is a first screen and further comprising
peeling the first screen to remove it from the pressure-sensitive adhesive; and
applying a second scintillator screen onto the pressure-sensitive adhesive, wherein the second scintillator screen is different from the first scintillator screen and includes characterisitics for a second different type of radiographic image than the first scintillator screen.
22. The method of claim 18 wherein the dry-form sheet pressure sensitive adhesive does not receive additional activation or curing.