Organic light emitting diode with color-correction for maximum white-point color shift

Patent metadata

Field	Value
Publication number	US-12007593-B2
Application number	US-201917044367-A
Country	US
Kind code	B2
Filing date	Apr 9, 2019
Priority date	Apr 18, 2018
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

An OLED display including a display panel and a color-correction component is described. A plurality of comparative display panels otherwise equivalent to the display panel but having one or more different optical thicknesses of OLED layers have a maximum white-point color shift from 0 to 45 degrees of WPCS C 45 and a white-point axial efficiency of WPAE C . The plurality of comparative display panels defines a performance curve along a boundary of performance points. The OLED display and the display panel have respective maximum white-point color shifts from 0 to 45 degrees of WPCS 45 and WPCS 0 45 and respective white-point axial efficiencies of WPAE and WPAE 0 . WPCS 0 45 and WPAE 0 defines a performance point of the display panel to the right of the performance curve and WPCS 45 and WPAE defines a performance point of the OLED display above or to the left of the performance curve. Methods of making the OLED display are described.

First claim

What is claimed is:

1. An organic light emitting diode (OLED) display comprising:
a pixelated OLED display panel having a maximum white-point color shift as a view angle varies from 0 to 45 degrees of WPCS 0 45 and a white-point axial efficiency of WPAE 0 , the pixelated OLED display panel comprising a plurality of pixels, each pixel comprising a plurality of subpixels, each subpixel comprising a plurality of OLED layers; and
a color-correction component disposed on the pixelated OLED display panel, the color-correction component configured such that the display has a maximum white-point color shift as a view angle varies from 0 to 45 degrees of WPCS 45 and a white-point axial efficiency of WPAE,
wherein each comparative display panel in a plurality of comparative display panels otherwise equivalent to the pixelated OLED display panel but having one or more different optical thicknesses of the OLED layers has a maximum white-point color shift as a view angle varies from 0 to 45 degrees of WPCS C 45 and a white-point axial efficiency of WPAE, the plurality of comparative display panels defining a first performance curve along a boundary of performance points in WPCS C 45 -WPAE C space,
wherein a plurality of comparative displays otherwise equivalent to the display but having one or more different optical thicknesses of the OLED layers defines a second performance curve along a boundary of performance points in WPCS C 45 -WPAE C space, the second performance curve being above or to the left of the first performance curve, WPCS 45 and WPAE defining a performance point of the display substantially along the second performance curve,
wherein the second performance curve and the plurality of comparative displays defines a third performance curve in WPCS C 45 -WPAE C space such that for each comparative display in the plurality of comparative displays having a performance point along the second performance curve, removing the color-correction component from the comparative display results in a comparative display panel having a performance point along the third performance curve, the third performance curve being to the right of the first performance curve, WPCS 0 45 and WPAE 0 defining a performance point of the display panel substantially along the third performance curve.

2. The display of claim 1 , wherein WPCS C 45 of a first comparative display panel in the plurality of comparative display panels is no more than WPCS 0 45 -0.005, WPAE C of the first comparative display panel is no less than WPAE 0 -1 Cd/A, and WPCS 45 is less than WPCS C 45 of the first comparative display panel.

3. The display of claim 2 , wherein the plurality of subpixels includes a plurality of blue subpixels, each blue subpixel having a hole transport layer, a thickness of the hole transport layer of the blue subpixel being 1.02 to 1.1 times a thickness of a hole transport layer of a corresponding blue subpixel in the first comparative display panel.

4. The display of claim 1 , wherein a blue axial efficiency BAE of the display is at least 10% greater than a blue axial efficiency BAE C of a first comparative display panel in the plurality of comparative display panels having a performance point along the second performance curve and having a white-point axial efficiency within 5% of WPAE.

5. The display of claim 1 , wherein the pixelated OLED display panel has a maximum blue-point color shift as a view angle varies from 0 to 45 degrees of BPCS 0 45 and a blue axial efficiency of BAE 0 , the color-correction component being configured such that the display has a maximum blue-point color shift as a view angle varies from 0 to 45 degrees of BPCS 45 and a blue axial efficiency of BAE, a first comparative display panel in the plurality of comparative display panels having a maximum blue-point color shift as a view angle varies from 0 to 45 degrees of BPCS C1 45 and a blue axial efficiency of BAE C1 , BPCS C1 45 being within 0.0025 of BPCS 45 and BAE being at least 10% greater than BAE C1 .

6. The display of claim 1 , wherein the pixelated OLED display panel has a maximum blue-point color shift as a view angle varies from 0 to 45 degrees of BPCS 0 45 and a blue axial efficiency of BAE 0 , the color-correction component being configured such that the display has a maximum blue-point color shift as a view angle varies from 0 to 45 degrees of BPCS 45 and a blue axial efficiency of BAE, a first comparative display panel in the plurality of comparative display panels having a maximum blue-point color shift as a view angle varies from 0 to 45 degrees of BPCS C1 45 and a blue axial efficiency of BAE C1 , BAE C1 being within 5% of BAE and BPCS C1 45 being at least 0.005 greater than BPCS 45 .

7. The display of claim 1 , wherein the pixelated OLED display panel has a ratio of blue-to-red color mixing weights at 30 degrees of β 0 30 and a ratio of blue-to-red color mixing weights at 45 degrees of β 0 45 such that β 0 45 >β 0 30 ≥1.05 and 1.5≥β 0 45 ≥1.1, and wherein the color-correction component is configured such that a ratio of blue-to-red color mixing weights at 45 degrees of the display is β 45 and a ratio of blue-to-red color mixing weights at 30 degrees of the display is β 30 such that β 0 45 −0.1≥β 45 ≥2.1−β 0 45 and β 0 30 −0.05≥β 30 ≥2.05−β 0 30 .

8. The display of claim 7 , wherein 1.06≥β 45 ≥0.94 and 1.05≥β 30 ≥0.95.

9. The display of claim 1 , wherein the color-correction component comprises a wavelength and polarization dependent partial reflector comprising an optical stack, the optical stack comprising a plurality of optical repeat units, each optical repeat unit including first and second polymer layers, a refractive index difference between the first and second polymer layers along a first axis being Δny, a refractive index difference between the first and second polymer layers along an orthogonal second axis being Δnx, |Δnx| being at least 0.1 and |Δny| being no more than 0.04, wherein for refractive indices along the second axis, the optical repeat units have a smallest optical thickness T1 proximate a first side of the optical stack and a largest optical thickness T2 proximate an opposite second side of the optical stack, (T2−T1)/(T2+T1) being in a range of 0.05 to 0.2, T2 being at least 350 nm and no more 1250 nm.

10. The display of claim 1 , wherein the color-correction component comprises a color-correction film, the color-correction film comprising:
a plurality of microlayers, each microlayer having a maximum difference among its three orthogonal refractive indices at 550 nm is less than or equal to 0.05, each microlayer having an average refractive index being the arithmetic average of the three orthogonal refractive indices at 550 nm;
wherein the plurality of microlayers is configured into layer pairs of alternating high and low index microlayers, and wherein the average refractive index of each high index microlayer is between 0.15 and 0.75 more than the average refractive index of each low index microlayer;
wherein the layer pairs each have optical thicknesses at 550 nm between 150 nm and 550 nm, and at least half of the layer pairs have optical thicknesses at 550 nm between 275 nm and 400 nm;
wherein the color-correction film has few enough microlayers to transmit at least 80% of unpolarized visible light at normal incidence, photopically weighted; and
wherein the color-correction film has enough microlayers to reflect at least 15% of at least one wavelength of unpolarized light at 60 degrees incidence.

11. The display of claim 1 , wherein the color-correction component comprises a polymeric film, the polymeric film comprising a first polymeric la

Assignees

• 3M Innovative Properties Company

Inventors

• Erickson Nicholas C
• Freier David G
• Brott Robert L
• Hao Bing
• Rosen David A
• Menke Stephen M
• Chien Bert T
• Lee Seong Taek
• Hao Encai
• Yang Zhaohui
• Everaerts Albert I
• Lu Yongshang
• Kolb William Blake
• Bruesewitz Keith R
• Haag Adam D
• Park Sun-Yong
• Nevitt Timothy J
• Wheeler Brianna N
• Peterson Jody L
• Benoit Gilles J

Classifications

• H10K59/50

  OLEDs integrated with light modulating elements, e.g. with electrochromic elements, photochromic elements or liquid crystal elements · CPC title

• H10K59/35

  comprising red-green-blue [RGB] subpixels · CPC title

• A23K10/18

  of live microorganisms · CPC title

• C12N1/14

  Fungi (culture of mushrooms A01G18/00; as new plants A01H15/00); Culture media therefor · CPC title

• C12N11/14

  Enzymes or microbial cells immobilised on or in an inorganic carrier · CPC title