A perovskite-based solar cell comprising a transparent electrode disposed on a buffer layer that protects the perovskite from damage during the deposition of the electrode is disclosed. The buffer material is deposited using either low-temperature atomic-layer deposition, chemical-vapor deposition, or pulsed chemical-vapor deposition. In some embodiments, the perovskite material is operative as an absorption layer in a multi-cell solar-cell structure. In some embodiments, the perovskite material is operative as an absorption layer in a single junction solar cell structure.

A polymer solar cell includes a photoactive layer, a cathode electrode, and an anode electrode. The photoactive layer includes a polymer layer and a carbon nanotube layer. The polymer layer includes a first polymer surface and a second polymer surface opposite to the first polymer surface. A portion of the carbon nanotube layer is embedded in the polymer layer, and another portion of the carbon nanotube layer is exposed from the polymer layer. The cathode electrode is located a surface of the carbon nanotube layer away from the polymer layer. The anode electrode is located on the first polymer surface and spaced apart from the carbon nanotube layer. The entire second polymer surface is exposed.

A photoelectric conversion element includes a substrate, a first electrode, an electron-transporting layer, a photoelectric conversion layer, a hole-transporting layer, and a second electrode. The first electrode, the electron-transporting layer, the photoelectric conversion layer, the hole-transporting layer, and the second electrode are disposed on or above the substrate. The photoelectric conversion layer includes an organic material represented by General Formula (1) below, and a N-type semiconductor material.

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In the General Formula (1), R.sub.1 and R.sub.2 are each independently an alkyl group having 6 or more but 22 or less carbon atoms, n is each independently an integer of from 1 through 3, X is each independently a halogen atom, and m is each independently 1 or 2.

A display substrate has a display area, an opening area and an isolation area located between the display area and the opening area and surrounding the opening area, and the display area is disposed at least partially around the opening area. The display substrate includes a flexible base having a via hole located in the opening area. The flexible base includes an amorphous silicon layer. The amorphous silicon layer includes a first portion located in the isolation area and a second portion located in the display area, and a thickness of the first portion is greater than a thickness of the second portion.

A display device is provided. The display device includes a first substrate, a first detection electrode on the first substrate, a first bank including an opening that exposes the first detection electrode, a photosensitive layer on the first detection electrode, a second detection electrode on the photosensitive layer, a first electrode on the second detection electrode, a second bank including an opening that exposes the first electrode, a light emitting layer on the first electrode, a second electrode on the light emitting layer, a first optical system between the second detection electrode and the first electrode, and a second optical system on the second electrode, wherein the first optical system and the second optical system overlap the photosensitive layer in a thickness direction of the display device.

A display device is provided. The display device includes a first substrate, a first detection electrode on the first substrate, a first bank including an opening that exposes the first detection electrode, a photosensitive layer on the first detection electrode, a second detection electrode on the photosensitive layer, a first electrode on the second detection electrode, a second bank including an opening that exposes the first electrode, a light emitting layer on the first electrode, a second electrode on the light emitting layer, a first optical system between the second detection electrode and the first electrode, and a second optical system on the second electrode, wherein the first optical system and the second optical system overlap the photosensitive layer in a thickness direction of the display device.

A first solid-state imaging element according to an embodiment of the present disclosure includes a bottom-electrode; a top-electrode opposed to the bottom-electrode; a photoelectric conversion layer provided between the bottom-electrode and the top-electrode and including a first organic semiconductor material; and an upper inter-layer provided between the top-electrode and the photoelectric conversion layer, and including a second organic semiconductor material having a halogen atom in a molecule at a concentration in a range from 0 volume % or more to less than 0.05 volume %.

An imaging device includes: one or more pixels, each of the one or more pixels including a photoelectric converter including a first electrode, a second electrode, a photoelectric conversion layer that converts incident light into a signal charge, and a blocking layer; and a charge accumulation region that is coupled to the second electrode, and that accumulates the signal charge. An energy barrier of the blocking layer against migration of a charge having an opposite polarity to a polarity of the signal charge from the second electrode to the photoelectric conversion layer is larger than or equal to 1.8 eV, and an energy barrier of the blocking layer against migration of the charge from the photoelectric conversion layer to the second electrode is smaller than or equal to 1.6 eV.

An imaging apparatus includes a first electrode, a second electrode, and a photoelectric conversion layer located between the first electrode and the second electrode. The photoelectric conversion layer contains a first material, a second material, and a third material. The first material is a fullerene or a fullerene derivative. The second material is a donor-like organic semiconductor material. The average absorption coefficient in the visible light wavelength range of the third material is less than the average absorption coefficient in the visible light wavelength range of the first material.

A first solid-state imaging element according to an embodiment of the present disclosure includes a bottom-electrode; a top-electrode opposed to the bottom-electrode; a photoelectric conversion layer provided between the bottom-electrode and the top-electrode and including a first organic semiconductor material; and an—upper inter-layer provided between the top-electrode and the photoelectric conversion layer, and including a second organic semiconductor material having a halogen atom in a molecule at a concentration in a range from 0 volume % or more to less than 0.05 volume %.