Abstract: Radiation occurs when current is injected into an active layer from electrodes. A pair of clad layers is disposed sandwiching the active layer, the clad layer having a band gap wider than a band gap of the active layer. An optical absorption layer is disposed outside at least one clad layer of the pair of clad layers. The optical absorption layer has a band gap wider than the band gap of the active layer and narrower than the band gap of the clad layer. A spread of a spectrum of radiated light can be narrowed.

Abstract: A luminescence structure is formed on a substrate made of semiconductor or insulator. The luminescence structure has a lamination structure that an active layer made of semiconductor is sandwiched between a pair of clad layers made of semiconductor. The clad layer is made of the semiconductor having a band gap wider than an energy corresponding to a peak wavelength of an EL spectrum of the active layer. A carrier trap layer is disposed between the substrate and luminescence structure. A peak wavelength of an EL spectrum of the carrier trap layer is longer than a wavelength corresponding to a band gap of the substrate and the peak wavelength of the EL spectrum of the active layer. Electrodes are formed to inject current into the active layer.

Abstract: Radiation occurs when current is injected into an active layer from electrodes. A pair of clad layers is disposed sandwiching the active layer, the clad layer having a band gap wider than a band gap of the active layer. An optical absorption layer is disposed outside at least one clad layer of the pair of clad layers. The optical absorption layer has a band gap wider than the band gap of the active layer and narrower than the band gap of the clad layer. A spread of a spectrum of radiated light can be narrowed.

Abstract: A document processing device 100 is provided, the device 100 comprises an accessing part 110, a collecting part 120, a morpheme analysis part 130, an extracting part 140, a storing part 150, and a displaying part 160. The collecting part 120 collects evaluation comments aiming at a certain evaluation subject as a first evaluation comment group from the database 180, and collects evaluation comments, in which these evaluation comments are comments on evaluation subjects other than the said certain evaluation subject by valuers who provided evaluation comments on the said certain evaluation subject as a second evaluation comment group from the database 180. The morpheme analysis part 130 segments sentences included in the said first and second evaluation comment groups into pairs of an attribute having at least one predetermined keyword and an attribute value having at least one part of speech regarding the attribute using a morpheme analysis technique.