Abstract: An antenna device of simple structure and high performance which is capable of lessening a reduction of a converging efficiency of radio wave due to a window glass sheet or the like to which the antenna device is fitted, and capable of obtaining a high converging efficiency to a received radio wave. The antenna device comprises a fitted member (5) having transparency, a converging member (1) for converging a radio wave, a space between the fitted member (5) and the converging member (1), and a receiving portion for receiving the radio wave converged by the converging member (1) or a transmitting portion for radiating a radio wave to the converging member (1) wherein in a case that a receive power value is changed so as to take alternately a bottom value and a peak value depending on a change of the thickness of the space, the thickness of the space is adjusted so that the received power value does not take a value in the vicinity of bottom values.

Abstract: An antenna device of simple structure and high performance which is capable of lessening a reduction of a converging efficiency of radio wave due to a window glass sheet or the like to which the antenna device is fitted, and capable of obtaining a high converging efficiency to a received radio wave. The antenna device comprises a fitted member 5 having transparency, a converging member 1 for converging a radio wave, a space between the fitted member 5 and the converging member 1, and a receiving portion for receiving the radio wave converged by the converging member 1 or a transmitting portion for radiating a radio wave to the converging member 1 wherein in a case that a receive power value is changed so as to take alternately a bottom value and a peak value depending on a change of the thickness of the space, the thickness of the space is adjusted so that the received power value does not take a value in the vicinity of bottom values.

Abstract: A hed-up display comprises a light source and a liquid crystal display device for displaying an image, and a hologram arranged on a windshield glass of a vehicle to diffract the light to an observer, wherein the hologram has the half width of the diffraction spectrum so that a white light entering into the vehicle from the outside is diffracted as substantially a white light.

Abstract: An acrylonitrile polymer composition obtained by uniformly mixing an acrylonitrile polymer, water and acrylonitrile is heated at the autogeneous pressure or above and the resulting melt is shaped into a desired form. The shaping processability is improved thereby.