A multi-layered coating system for reflecting infrared waves is disclosed. The multi-layered coating system comprises a layer one positioned above a substrate, wherein the layer one includes a plurality of well separated spherical particulates of radius a1 and a plurality of well separated spherical voids of radius b1 > a1 that are randomly distributed, and a filler material of refractive index n1 intervening in the spaces between said spherical particulates and spherical voids; and subsequent layers expressible as the following word-equation, "a layer i positioned above the layer i-1, wherein the layer i includes a plurality of well separated spherical particulates of radius ai and a plurality of well separated spherical voids of radius bi > ai (where bi > bi-1) that are randomly distributed, and a filler material of refractive index ni intervening in the spaces between said spherical particulates and spherical voids," where integer i is greater than one.

Provided are a multilayered-coating system and a method of manufacturing the same. The multi-layered coating system includes: a layer 1 including a plurality of spherical voids with a radius a₁ that are randomly distributed and separated from one another and a filler material with a refractive index n₁ that is disposed in a space between the spherical voids; and subsequent layers expressed as the following word-equation, "a layer i located above a layer i-1 and including a plurality of spherical voids with a radius a_¡ that are randomly distributed and separated from one another, and a filler material with a refractive index n_i, the filler material disposed in a space between the spherical voids where i is an integer greater than 1".

An electromagnetic radiation generating device generates electromagnetic wave pulses (LT1) from a plane surface which receives pulsed light (LP1). The electromagnetic radiation generating device includes an electromagnetic radiation generating element (10), a light irradiating unit, and a reverse bias voltage applying circuit. The electromagnetic radiation generating element (10) includes a depletion layer forming body (90) formed by stacking a p-type silicon layer (14) and an n-type silicon layer (15) in a planar pattern having a pn junction (17), an antireflection film (16) and a light receiving surface electrode formed on the light receiving surface (10A) which is one surface of the depletion layer forming body (90), the light receiving surface electrode including a plurality of parallel electrode parts (121) that are equally spaced while the distance is maintained between the parallel electrode parts (121), the distance corresponding to the wavelength of the electromagnetic wave pulses (LT1) generated from the depletion layer forming body (90) and a rear surface electrode (13) formed on the rear surface (10B) which is the opposite surface of the depletion layer forming body (90). The reverse bias voltage applying circuit applies a voltage to bring a depletion layer formed in the depletion layer forming body into a reverse biased condition through the light receiving surface electrode and the rear surface electrode (13).

A liquid crystal optical element (1) is provided which is employed in a vehicle light (15), for example, having a light source (12), a reflector (13), and a lens (14). The liquid crystal optical element (1) is placed between the light source (12) and the lens (14), whereby light distribution control can be achieved over a wide range beyond a basic light distribution constituted by the light source (12), the reflector (13), and the lens (14). A liquid crystal having a photocurable liquid crystalline monomer added thereto is filled into a cell to form a liquid crystal layer (5), which is in turn irradiated with a stripe pattern of ultraviolet rays to partially cure and polymerize the monomer. This provides a cured grating portion (6) and a non-cured, non-grating portion (7) are formed. When a voltage is not applied to the liquid crystal optical element (1), this element (1) is in a transparent state due to the uniformity in the molecular arrangement and the refractive index of the grating portion (6) and the non-grating portion (7) adjacent to each other. When a voltage is applied, the light guided inside the liquid crystal layer (5) is refracted in a predetermined direction by means of the difference in refractive index between the grating portion (6) and the non-grating portion (7) to thereby form scattered light. This can extend projection direction range to the outside.

A method of micro-structuring a surface of a sample of ferroelectric material, the method comprising: (a) taking a sample of ferroelectric material having a -z face which is to be etched; (b) illuminating the -z face with ultraviolet light to define illuminated and unilluminated parts of the surface; and (c) immersing the -z face in an etchant to selectively remove the unilluminated parts of the -z face at a greater rate than the illuminated parts. The method can be carried out using pulsed ultraviolet light to etch lithium niobate crystals cut for etching on the -z face, and may further be combined with ablation to produce multi-level surface structures.