2237results about How to "Reduce unevenness" patented technology

In a selective growth method, growth interruption is performed at the time of selective growth of a crystal layer on a substrate. Even if the thickness distribution of the crystal layer becomes non-uniform at the time of growth of the crystal layer, the non-uniformity of the thickness distribution of the crystal layer can be corrected by inserting the growth interruption. As a result of growth interruption, an etching rate at a thick portion becomes higher than that at a thin portion, to eliminate the difference in thickness between the thick portion and the thin portion, thereby solving the problem associated with degradation of characteristics due to a variation in thickness of the crystal layer, for example, an active layer. The selective growth method is applied to fabrication of a semiconductor light emitting device including an active layer as a crystal layer formed on a crystal layer having a three-dimensional shape by selective growth.

A portable terminal monitors a signal level of a short-range wireless signal from a wireless communication apparatus. If the signal level drops so low that a state of connection for short-range wireless communications cannot be maintained between the two apparatuses, use of predetermined functions of the portable terminal is limited. A short-range wireless communication facility of the portable terminal and the wireless communication apparatus move into a particular operation mode if communications do not occur therebetween at least for a predetermined time period. In monitoring the signal level of the wireless signal from the wireless communication apparatus in the particular operation mode, the portable terminal reduces a response speed at which to detect a signal level change. This causes the wireless communication apparatus to delay issuing a request for an increase in transmission power, thereby reducing unevenness of the working distance at which to alert a user to the unusual distance traveled between the two apparatuses or beyond which to limit the use of some functions of the portable terminal.

An optical device including an optical waveguide upon which a group of parallel light beams different in traveling direction from each other are incident and from which the group of parallel light beams go out after propagated by repeated total reflection through it. The optical waveguide includes a first reflection-type volume hologram grating, and a second reflection-type volume hologram grating. The pitches of interference fringes on the hologram surfaces of the first and second reflection-type volume hologram gratings are equal to each other. In at least the second reflection-type volume hologram grating, the angle formed between the interference fringes and hologram surfaces are varied continuously or stepwise within the hologram in relation to the main incident light beam so as to meet the Bragg condition. Therefore, it is possible to reduce the unevenness of color and brightness due to angles of view.

A light emitting device comprises: an LED chip mounted in a recess formed in a mounting substrate; a wavelength converting member that is disposed so as to cover the recess and the edge area around the recess and that is excited by light emitted from the LED chip to emit light of a wavelength different from an excitation wavelength; and an emission control member disposed at a light output side of the wavelength converting member so as to allow emission of light coming from an area of the wavelength converting member that corresponds to the recess and to prevent emission of light coming from an area of the wavelength converting member that corresponds to the edge area around the recess. This can prevent variations in color between light emitted from the central part of the wavelength converting member and light emitted from the part of the wavelength converting member that is located on the edge area around the recess of the mounting substrate, thereby reducing unevenness of color on the irradiation surface.

Disclosed are: an etching solution for a multilayer thin film having a copper layer and a molybdenum layer contained therein; and a method for etching a multilayer thin film having a copper layer and a molybdenum layer contained therein using the etching solution. Specifically disclosed are: an etching solution for a multilayer thin film having a copper layer and a molybdenum layer contained therein, which comprises (A) hydrogen peroxide, (B) an inorganic acid having no fluorine atom, (C) an organic acid, (D) an amine compound having 2 to 10 carbon atoms and also having an amino group and a hydroxy group in the total number of two or more, (E) an azole, and (F) a hydrogen peroxide stabilizer, and which has a pH value of 2.5 to 5; and an etching method using the etching solution.