Light-emitting element and organic electroluminescent display device

A light-emitting element, comprising:

• (A) a first electrode;
• (B) an organic layer including a light-emitting layer made of an organic light-emitting material;
• (C) a semi-transmissive/reflective film;
• (D) a resistance layer;
• and
• (E) a second electrode,
• wherein,
• the first electrode is configured to reflect light coming from the light-emitting layer,
• the second electrode is configured to transmit light coming from the semi-transmissive/reflective film after passing through the semi-transmissive/reflective film, and
• when a distance from a first interface between the first electrode and the organic layer to a position on the light-emitting layer where a level of light emission is maximum is L1, an optical distance thereof is OL1, a distance from a second interface between the semi-transmissive/reflective film and the organic layer to a position on the light-emitting layer where a level of light emission is maximum is L2, and an optical distance thereof is OL2, expressions (1-1) and (1-2) below are satisfied,
• 0.7{−Φ1/(2π)+m1}≦2×OL1/λ≦1.2{−Φ1/(2π)+m1} (1-1)
• 0.7{−Φ2/(2π)+m2}≦2×OL2/λ≦1.2{−Φ2/(2π)+m2} (1-2)
• where λ is a maximum peak wavelength in a spectrum of a light generated in the light-emitting layer,
• Φ1 is an amount of phase shift (unit:
• radian) of a reflected light generated on the first interface (where −2π<φ1<0)
• Φ2 is an amount of phase shift (unit:
• radian) of a reflected light generated on the second interface (where −2π<Φ2<0), and
• a value of (m1, m2) is (0, 0), (1, 0), or (0, 1).

A light-emitting element, comprising:

• (A) a first electrode;
• (B) an organic layer including a light-emitting layer made of an organic light-emitting material;
• (C) a semi-transmissive/reflective film;
• (D) a resistance layer;
• and
• (E) a second electrode,
• wherein,
• the first electrode is configured to reflect light coming from the light-emitting layer,
• the second electrode is configured to transmit light coming from the semi-transmissive/reflective film after passing through the semi-transmissive/reflective film, and
• when an optical distance between a first interface between the first electrode and the organic layer and a second interface between the semi-transmissive/reflective film and the organic layer is L, a sum of phase shift to be observed when a light generated in the light-emitting layer is reflected on the first and second interfaces is 4 radian, and a maximum peak wavelength in a spectrum of the light generated in the light-emitting layer is λ,
• an expression of
• 0.7<{(2L)/λ+Φ/(2π)}<1.3
• or
• −0.3<{(2L)/λ+Φ/(2π)}<0.3
• is satisfied.

An organic electroluminescent display device, including a plurality of organic electroluminescent elements each comprising:

• (a) a first electrode;
• (b) an insulation layer including an aperture, and from a bottom portion of the aperture, the first electrode is exposed;
• (c) an organic layer disposed from the above of a portion of the first electrode exposed from the bottom portion of the aperture to a portion of the insulation layer around the aperture, and includes a light-emitting layer made of an organic light-emitting material;
• (d) a semi-transmissive/reflective film formed at least on the organic layer;
• (e) a resistance layer covering the semi-transmissive/reflective film;
• and
• (f) a second electrode formed on the resistance layer,
• wherein,
• the first electrode reflects a light coming from the light-emitting layer,
• the second electrode passes through a light coming from the semi-transmissive/reflective film after passing therethrough, and
• a portion of the semi-transmissive/reflective film on the insulation layer is at least partially discontinuous.