Organic EL device and electronic apparatus

• US 8,547,014 B2
• Filed: 09/10/2009
• Issued: 10/01/2013
• Est. Priority Date: 10/03/2008
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Watanabe, Shotaro, Uchida, Masahiro
• Primary Examiner(s): Hines, Anne
• Assistant Examiner(s): DIAZ, JOSE
• Application Number:
  US12/557,200
• Publication Number:
  US 20100084968A1
• Time in Patent Office: 1,482 Days
• Field of Search: 313498-512
• US Class Current: 313/506
• CPC Class Codes: H10K 2102/3031 Two-side emission, e.g. transparent OLEDs [TOLED]
• CPC Class Codes: H10K 2102/351 Thickness
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 59/876 comprising a resonant cavity structure, e.g. Bragg reflector pair

Abstract

An organic EL device includes an organic EL element that includes an anode having a reflective face, a cathode having a semi-transmissive reflective layer, and a functional layer, which is pinched between the anode and the cathode and includes at least an organic light emitting layer, and configures a color pixel that implements light emission corresponding to at least a red color. The color pixel configured by the organic EL element forms an optical resonator between the reflective face of the anode and the semi-transmissive reflective layer of the cathode. The color pixel corresponding to the red color has a film thickness profile of the functional layer in a convex shape in which a center portion is relatively thick, and a periphery portion is relatively thin or a concave shape in which the center portion is relatively thin, and the periphery portion is relatively thick.

Claims

1. An organic EL device comprising an organic EL element that includes an anode having a reflective face, a cathode having a semi-transmissive reflective layer, and a functional layer, which is pinched between the anode and the cathode so that the cathode is in contact with the functional layer and at least one partition wall portion, and includes at least an organic light emitting layer, and configures a color pixel that implements light emission corresponding to at least a red color,

wherein the color pixel configured by the organic EL element forms an optical resonator between the reflective face of the anode and the semi-transmissive reflective layer of the cathode,

wherein the color pixel corresponding to the red color has a film thickness profile of the functional layer in a concave shape in which the center portion is relatively thin, and the periphery portion is relatively thick, and the film thickness R(a) of the peripheral portion of the concave-shaped functional layer satisfies equations (1) and (2) relating to the length d1 of a resonance light path of the optical resonator,

2d1=mλ

+(θ

an*λ

)/2π

+(θ

ca*λ

)/2π

 

 

equation (1);

here, m is an integer, λ

is a peak wavelength of the spectrum of light desired to be emitted, θ

an is the amount of phase shift in the case of reflection from the anode side, and θ

ca is the amount of phase shift in the case of reflection from the cathode side;

0.9d1≦

R(a)≦

1.1d1, and 

 

equation (2);

wherein the organic EL elements configure color pixels that implement light emission corresponding to at least the red color and the blue color, wherein the color pixel corresponding to the blue color has a film thickness profile of the functional layer in a convex shape in which the center portion is relatively thick, and the periphery portion is relatively thin.

3. The organic EL device according to claim 1, wherein the functional layer is formed by using a liquid droplet ejecting method.

4. An electronic apparatus comprising the organic EL device according to claim 1.

2. An organic EL device comprising an organic EL element that includes an anode having a reflective face, a cathode having a semi-transmissive reflective layer, and a functional layer, which is pinched between the anode and the cathode so that the cathode is in contact with the functional layer and at least one partition wall portion, and includes at least an organic light emitting layer, and configures a color pixel that implements light emission corresponding to at least a blue color,

wherein the color pixel configured by the organic EL element forms an optical resonator between the reflective face of the anode and the semi-transmissive reflective layer of the cathode, and

wherein the color pixel corresponding to the blue color has a film thickness profile of the functional layer in a concave shape in which a center portion is relatively thin, and a periphery portion is relatively thick, and the film thickness B(a) of the peripheral portion of the convex-shaped functional layer satisfies Equations (1) and (3) relating to the length d1 of a resonance light path of the optical resonator,

2d1=mλ

+(θ

an*λ

)/2π

+(θ

ca*λ

)/2π

 

 

equation (1);

here, m is an integer, λ

is a peak wavelength of the spectrum of light desired to be emitted, θ

an is the amount of phase shift in the case of reflection from the anode side, and θ

ca is the amount of phase shift in the case of reflection from the cathode side;

0.9d1≦

B(a)≦

1.1d1, 

 

equation (3);

wherein the organic EL elements configure color pixels that implement light emission corresponding to at least the blue color and the red color,

wherein the color pixel corresponding to the red color has a film thickness profile of the functional layer in a convex shape in which the center portion is relatively thick, and the periphery portion is relatively thin, and the film thickness R(a) of the center portion of the convex-shaped functional layer satisfies the equation (1) and equation (2) relating to the length d1 of the resonance light path of the optical resonator,

0.9d1≦

R(a)≦

1.1d1, 

 

equation (2).