Low blue light displays
View Patent ↗A display for emitting display light comprising: (a) a light source for emitting a source light; and (b) a filter positioned in the path of said source light, said filter comprising at least short, medium and long filters, wherein said short filter is configured to transmit short-primary light from said source light, said short-primary light comprising a violet portion having wavelengths from 400 to 440 nm and at least a second portion having wavelengths above 440 nm such that said short-primary light is perceptually blue, said short-primary light having a short-primary SPD having a short-primary power between 380-780 nm and a blue power between 440-500 nm, wherein said blue power is less than 5% of said short-primary power.
1. A display for emitting display light comprising:
a light source for emitting a source light; and
a filter positioned in the path of said source light, said filter comprising at least short, medium and long filters, wherein said short filter is configured to transmit short-primary light from said source light, said short-primary light comprising a violet portion having wavelengths from 400 to 440 nm and at least a second portion having wavelengths above 440 nm such that said short-primary light is perceptually blue, said short-primary light having a short-primary SPD having a short-primary power between 380-780 nm and a blue power between 440-500 nm, wherein said blue power is less than 20% of said short-primary power.
2. The display of claim 1 , wherein said light source comprises a violet solid-state emitter for emitting pump light having a peak wavelength below 430 nm.
3. The display of claim 2 , wherein said short-primary light has a dominant wavelength and said peak wavelength is at least 30 nm shorter than said dominant wavelength.
4. The display of claim 3 , wherein said dominant wavelength is above 440 nm.
5. The display of claim 4 , wherein said dominant wavelength is above 460 nm.
6. The display of claim 2 , wherein said source light has a source light SPD having a source power between 380-780 nm and a source blue power between 440-500 nm, wherein said source blue power is less than 5% of said source power.
7. The display of claim 6 , wherein,
said light source comprises one or more solid state light emitters comprising at least a violet solid-state emitter emitting pump light with a peak wavelength in a range 400-430 nm:
one or more wavelength converting materials comprising at least a first wavelength-conversion material configured to absorb a portion of said pump light and to convert said portion to converted light, said first wavelength-conversion material having a first absorption coefficient at said peak wavelength, and a second absorption coefficient at 450 nm, wherein said first absorption coefficient is less than 70% of said second absorption coefficient;
wherein said one or more solid state emitters and said one or more wavelength-conversion materials are configured such that said first wavelength-conversion material does not substantially absorb light between 440-490 nm; and
wherein said emitted light is substantially white light essentially free of blue light.
8. The display of claim 1 , wherein said short filter is configured to block a substantial portion of said source light in the range 440-500 nm while transmitting said violet and second portions.
9. The display of claim 1 , wherein said medium filter is configured to transmit medium-primary light from said source light, and said long filter is configured to transmit long-primary light from said source light, wherein the combination of said short-primary light, said medium-primary light, and said long-primary light is substantially white light.
10. The display of claim 9 , wherein said medium-primary light is perceptually green, and said long-primary light is perceptually red.
11. The display of claim 1 , wherein, when said short, medium, and long filters are fully transmitting, said display light is substantially white light with a display SPD having a display power between 380-780 nm, and display blue power between 440-500 nm, wherein said display blue power is less than 5% of said display power.
12. The display of claim 11 , wherein said filter is configured such that at least 40% of said display power is below the wavelength of 430 nm.
13. The display of claim 11 , wherein said substantially white light is within an (x, y) distance less than 0.03 from a D65 chromaticity.
14. The display of claim 11 , wherein said display has a gamut which is at least 90% of DCI-P3 (calculated in (xy)).
15. The display of claim 1 , wherein said second portion has a second portion SPD having a second portion power between 440-780 nm, wherein at least 80% of said second portion power is in the range 490-780 nm.
16. The display of claim 15 , wherein at least 80% of said second portion power is within a wavelength range 500-540 nm.
17. The display of claim 1 , wherein said short filter is configured such that at least 10% of said short-primary power is in a range 490-780 nm.
18. The display of claim 17 , wherein said short filter is configured such that at least 20% of said short-primary power is in a range 500-780 nm.
19. The display of claim 1 , wherein the short filter has a transmission at a wavelength of 500 nm which is at least 30% of its transmission at said pump wavelength.
20. The display of claim 2 , wherein the violet solid-state emitter is selected from one of an LED, a laser diode, or an OLED.
21. The display of claim 1 , wherein said display defines a plurality of pixels comprising subpixels, each subpixel comprising one of said short, medium and long filters.
22. The display of claim 21 , wherein each of said pixels comprising subpixels having each of said short, medium and long filters.
23. A light source for emitting emitted light, said light source comprising:
one or more solid state light emitters comprising at least a violet solid-state emitter emitting pump light with a peak wavelength in a range 400-430 nm:
one or more wavelength converting materials comprising at least a first wavelength-conversion material configured to absorb a portion of said pump light and to convert said portion to converted light, said first wavelength-conversion material having a first absorption coefficient at said peak wavelength, and a second absorption coefficient at 450 nm, wherein said first absorption coefficient is less than 70% of said second absorption coefficient;
wherein said one or more solid state emitters and said one or more wavelength-conversion materials are configured such that said first wavelength-conversion material does not substantially absorb light between 440-490 nm; and
wherein said emitted light is substantially white light essentially free of blue light.
24. The light source of claim 23 , wherein said one or more wavelength converting materials are configured to leak a second portion of said pump light such that said emitted light comprises said second portion.
25. The light source of claim 23 , wherein said first wavelength converting material is configured not to absorb a second portion of said pump light.
26. The light source of claim 23 , wherein said emitted light has an SPD having an emitted power between 380-780 nm and a violet power between 400-440 nm, wherein said violet power is at least 20% of said emitted power.
27. The light source of claim 26 , wherein said violet power is at least 40% of said emitted power.
28. The light source of claim 26 , wherein said one or more solid state emitters and said wavelength-conversion materials are configured to provide package efficiency for the light source of at least 70%.
29. The light source of claim 28 , wherein said package efficiency is at least 85%.
30. The light source of claim 23 , wherein said emitted light has an emitted light SPD having an emitted power between 380-780 nm and a violet power between 400-430 nm, and a blue power between 440-500 nm, wherein said violet power is at least 20% of said emitted power and said blue power is less than 5% of said emitted power.
31. The light source of claim 30 , wherein said blue power is less than 10% of said violet power.
32. The light source of claim 23 , wherein said first wavelength-conversion material has a maximum peak absorption coefficient outside of said range.
33. The light source of claim 32 , wherein said maximum peak absorption coefficient is between 440 and 490 nm.
34. The light source of claim 32 , wherein said emitted light has an SPD with a local minimum within +/−25 nm of the wavelength corresponding to said maximum peak absorption coefficient.
35. The light source of claim 23 , wherein said first wavelength conversion material is one of KSF or MFG.
36. The light source of claim 23 , wherein the violet solid-state emitter is selected from one of an LED, a laser diode, an OLED.
37. A display comprising the light source of claim 23 plus a second light source that emits substantial light between 440-490 nm.
38. A display comprising the light source of claim 23 , wherein said display is configured to emit a display light when set to display a white point, said display light being substantially white light.
39. The display of claim 38 , wherein said display light has a CCT above 4000K.
40. The display of claim 38 , where the display light has a display SPD having a white display power between 380-780 nm and a blue display power between 440-500 nm, wherein said blue display power is less than 5% of said white display power.