Strongly scattering ceramic converter and method for producing same
A strongly scattering optoceramic converter material having a density of less than 97% is provided, as well as a method for producing such an optoceramic material. By appropriately choosing in particular the composition, blending method, and sintering conditions, the production method permits to produce converter materials with tailored properties.
1. A single-phase porous optoceramic, comprising:
a ceramic phase A 3 B 5 O 12 , wherein A is selected from a group consisting of Y, Gd, Lu, and combinations thereof, wherein B is selected from a group consisting of Al, Ga, and combinations thereof, and wherein the ceramic phase A 3 B 5 O 12 comprises Ce as at least one active element;
a density, based on a theoretical density, of between 90 and 96.5% with pores having a polygonal shape; and
particles not integrated into the ceramic phase A 3 B 5 O 12 that are in a range from 0 vol % to less than 5 vol %,
wherein the optoceramic is configured to at least partially convert excitation light having a first wavelength into emitted light having a second wavelength, wherein the emitted light is emitted from a side of the optoceramic on which the excitation light is incident,
wherein the optoceramic is configured to remit and combine at least a portion of the excitation light with the emitted light,
wherein the optoceramic exhibits, when measured at a sample thickness of 1 mm, a remission at 600 nm that is from 0.75 to 0.95,
wherein the optoceramic is configured for operation in remission, and
wherein the optoceramic exhibits a quantum efficiency that is greater than 85%.
2. The optoceramic of claim 1 , wherein the particles not integrated into the ceramic phase A 3 B 5 O 12 are less than 1.5 vol %.
3. The optoceramic of claim 1 , wherein the pores have a mean pore size from 0.1 to 100 micrometers.
4. The optoceramic of claim 1 , wherein the ceramic phase A 3 B 5 O 12 mainly comprises Y 3 Al 5 O 12 .
5. The optoceramic of claim 1 , wherein the ceramic phase A 3 B 5 O 12 mainly comprises Lu 3 Al 5 O 12 .
6. The optoceramic of claim 1 , wherein the ceramic phase A 3 B 5 O 12 comprises yttrium and/or lutetium as a first element A and gadolinium as a second element A.
7. The optoceramic of claim 6 , wherein the gadolinium comprises Gd 2 O 3 and has a content with respect to the A site that is from 0.5 to 8 mol %.
8. The optoceramic of claim 1 , wherein A comprises Gd 2 O 3 in a content with respect to the A site that is from 0.5 to 8 mol %.
9. The optoceramic of claim 1 , wherein the ceramic phase A 3 B 5 O 12 comprises aluminum as a first element B and gallium as a second element B.
10. The optoceramic of claim 9 , wherein the gallium comprises Ga 2 O 3 and has a content with respect to the B site that is from 0.5 to 15 mol %.
11. The optoceramic of claim 1 , wherein B comprises Ga 2 O 3 in a content with respect to the A site that is from 0.5 to 15 mol %.
12. The optoceramic of claim 1 , wherein the Ce has a content from 0.001 to 3 wt %.
13. The optoceramic of claim 1 , wherein the Ce has a content from 0.01 to 3 wt %.
14. The optoceramic of claim 1 , further comprising a further active element selected from the group consisting of Pr, Sm, and Tb.
15. The optoceramic of claim 1 , further comprising a thickness from 150 to 250 micrometers.