Abstract: The state of a polysilicon film formed by excimer laser annealing an amorphous silicon film is to be evaluated. When the amorphous silicon film is annealed to form a polysilicon film, linearity or periodicity presents itself in the spatial structure of the film surface of the polysilicon film formed depending on the energy applied to the amorphous silicon during annealing. This linearity or periodicity is processed as an image and represented numerically from the image by exploiting the linearity or periodicity. The state of the polysilicon film is checked based on the numerical results.

Abstract: In a method of fabricating a thin film transistor through conversion of an amorphous silicon film into a polysilicon film to be an active layer of the thin film transistor by a laser annealing treatment, a laser annealing apparatus comprising a plurality of semiconductor laser devices arranged performs the laser annealing treatment by irradiating the surface of the amorphous silicon film with laser light uniformized in the light intensity of the laser light radiated onto the surface of the amorphous silicon film, whereby the crystal grain diameter of the polysilicon film obtained through recrystallization is uniformized, and it is possible to obtain a thin film transistor with transistor characteristics enhanced by using the polysilicon film as the active layer.

Abstract: An ultraviolet optical device includes optical parts on which an ultraviolet ray is irradiated. Some or all of the optical parts are arranged in an envelope having a gas inlet port and a gas output port. In the envelope (9), a dry gas having an amount of moisture (as volume fraction) of 5,000 [ppm] or less and led from the gas inlet port (10) is sprayed on an optical part in which at least a deterioration in optical characteristics is especially a problem, so that an improvement in the secular change of the optical part can be achieved.

Abstract: A method of evaluating a state of a polysilicon film objectively, accurately, automatically, and in a non-contact manner is provided. The method includes the steps of picking up a surface of a polysilicon film formed by excimer laser annealing, dividing the picked-up image into meshes each having a specific size, calculating a contrast in each of the meshes, extracting a highest contrast value and a lowest contrast value in the picked-up image, calculating a contrast ratio therebetween, and judging an average grain size of the polysilicon film on the basis of the contrast ratio.

Abstract: A polysilicon film evaluation apparatus is provided which enables objective automatic evaluation of the status of a polysilicon film, as formed to a high accuracy in a contact-free fashion.

Abstract: The state of a polysilicon film formed by excimer laser annealing an amorphous silicon film is to be evaluated. When the amorphous silicon film is annealed to form a polysilicon film, linearity or periodicity presents itself in the spatial structure of the film surface of the polysilicon film formed depending on the energy applied to the amorphous silicon during annealing. This linearity or periodicity is processed as an image and represented numerically from the image by exploiting the linearity or periodicity. The state of the polysilicon film is checked based on the numerical results.

Abstract: Disclosed is a method for the growth of a single crystal having excellent crystallinity, uniform quality in the inside thereof and hence excellently uniform optical properties, the method enabling an improvement in yields. The invention resides in a method for the growth of a single crystal of &bgr;-type barium borate (&bgr;-BaB2O4), the method comprising heating a crucible 6 indirectly to grow a &bgr;-BaB2O4 single crystal 21 from a melt of barium borate (BaB2O4) contained in the crucible and using no flux by using a seed crystal 9 of &bgr;-BaB2O4.

Abstract: A laser beam generating apparatus comprising a first laser beam source oscillating in a near infrared-ray region of, for example, an Nd:YAG laser to generate a laser beam, a second higher harmonic wave generator for generating, from the laser beam emitted from the first laser beam source, a second higher harmonic wave having a half wavelength of the laser beam emitted from the first laser beam source, a splitter for splitting the second higher harmonic wave, a second laser beam source which is supplied with a part of the second higher harmonic wave thus split is input to a Ti:Sapphire laser to be excited and oscillated, thereby generating a laser beam of substantially 700 nm in wavelength, a fourth higher harmonic wave generator for generating a fourth higher harmonic wave from the remaining part of the second higher harmonic wave thus split, a sum frequency mixing composed of a BBO crystal device to which the laser beam of substantially 700 nm in wavelength and the fourth higher harmonic wave are input, and

Abstract: By polishing an optical device such as .beta.-BBO crystals using a liquid suspension comprising a fine powder of silicon oxide and a liquid lubricant of saturated hydrocarbon, satisfactory mirror face polishing can be applied to the optical device, without deteriorating the surface property while reducing occurrence of fine optical defects.

Abstract: An apparatus for generating ultraviolet laser radiation according to the present invention includes a laser light source and a frequency conversion device made of a nonlinear optical crystal on which laser light irradiated from the laser light source is made incident and which converts a frequency of the incident laser light to thereby irradiate the ultraviolet radiation. A protective film which prevents oxygen and water content from permeating thereinto is deposited on at least an output end surface, from which ultraviolet radiation is irradiated, of the nonlinear optical crystal. Therefore, it is possible to prevent characteristics of the frequency conversion device from being lowered due to change of a property thereof resulting from increased output power of laser light and to increase a lifetime thereof.

Abstract: A method of growing a single crystal of KTiOPO.sub.4 which is a nonlinear optical material is disclosed. Growth of the single crystal of KTiOPO.sub.4 is carried out by melting a KTiOPO.sub.4 material with a flux to produce a melt, then contacting a seed crystal to the melt, and by slowly cooling at a saturation temperature or below. At this time, molar fractions of K.sub.2 O, P.sub.2 O.sub.5 and TiO.sub.2 contained in the melt fall within a region surrounded by six point in a K.sub.2 O-P.sub.2 O.sub.5 -TiO.sub.2 ternary phase diagram of A (K.sub.2 O:0.4150, P.sub.2 O.sub.5 :0.3906, TiO.sub.2 : 0.1944), B (K.sub.2 O:0.3750, P.sub.2 O.sub.5 : 0.3565, TiO.sub.2 : 0.2685), C (K.sub.2 O: 0.3750, P.sub.2 O.sub.5 : 0.3438, TiO.sub.2 : 0.2813), D (K.sub.2 O: 0.3850, P.sub.2 O.sub.5 : 0.3260, TiO.sub.2 : 0.2890), E (K.sub.2 O: 0.4000, P.sub.2 O.sub.5 : 0.3344, TiO.sub.2 : 0.2656), and F (K.sub.2 O: 0.4158, P.sub.2 O.sub.5 : 0.3744, TiO.sub.2 : 0.2098). In addition, K.sub.15 P.sub.13 O.sub.

Abstract: A method is provided for producing a KTiOPO.sub.4 which is grown at a temperature higher than its Curie temperature using a TSSG method. The grown KTiOPO.sub.4 single crystal is maintained in contact with a melt while the crystal is maintained at a temperature higher than the Curie temperature. A d.c. current is applied in this state across a seed crystal and the melt, while the single crystal is cooled to a temperature lower than the Curie temperature. The value of current density D, defined by the formula D=Ip/(a+b), where Ip is the impressed current and a, b are crystal sizes along a and b axes, respectively, is selected to be 0.01 mA/cm.sup.2 .ltoreq.D.ltoreq.1.0 mA/cm.sup.2. In this manner, the produced KTiOPO.sub.4 is processed into a single domain crystal.

Abstract: A sequential access memory to be used as a data delaying device in a digital circuit. The sequential access memory is provided with a storage portion which is capable of storing the data of the (m.times.2+l) words, and a counter which has an (m.times.2+l.times.2) base returns to the (m+1) address after having accessed the addresses to the (m.times.2+l) address sequentially from the No. 1 of the storage portion, and accesses the address of No. 1 again after having accessed the addresses to the (m+l) address sequentially from the (m+1) address so as to repeat the similar counting operation. Therefore, the data of the two systems having a portion composed of the m words and the b portion composed of the l words may be outputted at a predetermined timing by a simplified, inexpensive circuit, which requires no output switching device.