Abstract: Disclosed in the present invention is a floating hologram system. The floating hologram system includes a diffuser configured to form a projection image using light beams transmitted from an image transmitter and diffuse the formed image, and a holographic optical element on which the image diffused from the diffuser is incident and which generates a virtual image floating at a position a predetermined distance therefrom and has a convex lens characteristic. A distance between the diffuser and the holographic optical element is determined based on a focal length of the holographic optical element and a distance from the holographic optical element to the virtual image.

Abstract: Provided is an organic chlorohydrosilane, a useful starting material for preparing silicon polymers and a method for preparing the same. More particularly, the present invention enables the synthesis of various novel organic chlorohydrosilanes in high yield by an exchange reaction between an Si—H bond of a chlorosilane which can be obtained in an inexpensive and easy manner and an Si—Cl bond of an another organic chlorosilane using a quaternary organic phosphonium salt compound as a catalyst. Since the catalyst can be recovered after its use and reused, the present invention is very economical and thus effective for mass-producing silicon raw materials.