39results about How to "Luminance unevenness" patented technology

An image reading apparatus includes a light source which irradiates an original with light, an imaging unit which images by condensing reflected and scattered light from the original via a plurality of reflecting mirrors and imaging mirrors, and a photoelectric conversion unit which converts, into an electrical signal, the reflected and scattered light imaged by the imaging unit. The imaging unit is an imaging optical system which is adjusted such that the difference between the spectral characteristic at an end portion in the main-scanning direction of the image reading apparatus and that at the central portion in the main-scanning direction becomes 5% or less at the peak wavelength of the light source.

A large-sized thin light guide plate has a first layer on a light exit surface side and a second layer on a rear surface side containing scattering particles at a higher particle concentration than the first layer. Thicknesses of the layers in a direction substantially perpendicular to the light exit surface change to change a combined particle concentration. The scattering particles, obtained by mixing a particle group with an average particle size Ds of less than 7 μm having one or more local maximum values and a particle group with an average particle size Db of more than 7 μm having one or more local maximum values, satisfy 1 μm≦Ds<7 μm, 7 μm<Db≦12 μm and 0.3≦a≦0.5. High light use efficiency, reduction of luminance and color unevenness, a convex brightness distribution and easy manufacture can be achieved.

A light-emitting device disclosed herein includes: an emission layer; a diffraction grating structure including a diffraction grating; and a diffusion layer having a structure for diffusing light which is transmitted from one face to another face. The light going out from the emission layer has a central wavelength λ. The diffraction grating has a period p which is not less than 1.0λ and not more than 3.5λ. The diffusion layer has a haze of 80% or more and a total light transmittance of 80% or less.

In a projection image displaying device which projects imaging light emitted from a projection lens by being reflected by a projection mirror, an air inlet for sucking external air is provided at the position of a sealing mechanism of the projection mirror. Air blown off through openings provided around the projection lens is sucked into a case through this air inlet. When a cooling operation of cooling components within the case is to be performed by sealing the projection mirror, a sucking operation through the air inlet is stopped. This prevents dust in the external air from adhering to a reflective surface of the projection mirror regardless of the installation state of the projection image displaying device.

A current inputted from a first input terminal and a reference current generated by an internal reference current generator circuit, which are in phase, are inputted to a reference current selector circuit by which either the inputted current or the reference current is selected. The selected current is temporarily phase-inverted by a current inverter circuit and drives a current mirror circuit of a current distributor circuit (or a reference current regulator circuit) for duplicating the reference current and distributing them. Currents, each of which is in phase with the reference current or the inputted current and has same current value as that of the reference current or the inputted current, can be generated in the output side transistors of the current mirror circuit. In order to realize this, a second output side transistor is provided in the current mirror circuit so that a current, which is in phase with the reference current and has substantially equal value to that of the selected current, is supplied from the output terminal to a next stage integrated circuit as an input reference current.

A first circuit generates first display data that is digital data which has information on luminance of an image displayed on a display portion. A second circuit generates second display data that is digital data obtained by converting a digital value of the first display data. A third circuit generates a first analog signal and a second analog signal whose potentials are calculated on the basis of the digital value of the first display data. The potential of the second analog signal is lower than the potential of the first analog signal. A fourth circuit converts the second display data into third display data that is analog data. A potential of the third display data is calculated on the basis of the potential of the first analog signal, the potential of the second analog signal, and a digital value of the second display data.

Provided is a display apparatus having a holding structure for an optical sheet capable of preventing wrinkles, bending, and sheet damage to the optical sheet in the display apparatus, and preventing defects such as irregular brightness and reduced brightness.A chassis for holding an optical sheet of a rectangular shape holds the peripheral edge part of the optical sheet at a holding surface of hollow rectangular shape, and has engaging parts to hold the optical sheet provided to stand at the edge part of one side of the holding surface. The holding surface is inclined or has a stepped protuberance formed, whereby the surface of the other region opposite of the end part of the one region on which the engaging parts is provided to stand is closer to the display panel than the surface of the one region of the holding surface within the height range of the engaging part, wherein the one region and the other region are present on the opposite side with respect to an opening of the holding surface.