Abstract: An apparatus for detecting materials includes a database for storing detecting spectra of detecting materials, and a tera-hertz wave applying unit for applying-tera-hertz waves having a plurality of different frequencies around a boundary between a light wave frequency and a radio wave frequency, to a predetermined position of an inspecting object. The apparatus includes an output wave receiving unit for receiving an output wave that is the tera-hertz wave having been applied to the inspecting object, and a determining unit for determining whether or not the output wave includes the detecting spectrum.

Abstract: An apparatus that inspects wire breaking of a semiconductor integrated circuit includes a voltage applying device (12), a light pulse source (14), a scanning device (16), an electromagnetic wave detection device (18), and a wire breaking detection device (20). The voltage applying device (12) maintains a semiconductor integrated circuit in a state where a predetermined voltage is being applied thereto. The light pulse source (14) generates an ultrashort light pulse (2). The scanning device (16) two-dimensionally scans and irradiates the two-dimensional circuit of the semiconductor integrated circuit by using the ultrashort light pulse (2). The electromagnetic wave detection device (18) detects an electromagnetic wave (3) radiated from a position irradiated with the ultrashort light pulse on the semiconductor integrated circuit. The wire breaking detection device (20) detects wire breaking of the irradiated position based on presence and absence or intensity of the electromagnetic wave.

Abstract: THz waves 4 on two different wavelengths are generated within a frequency range of about 0.5 to 3 THz, and a subject matter 10 is irradiated with the THz waves on two wavelengths to measure their transmittances, and thus the presence of a target having wavelength dependence on the absorption of the THz wave is detected from a difference of their transmittances. Furthermore, a surface of the subject. matter is scanned two-dimensionally with each of the THz waves on two different wavelengths, and an image of a position where the transmittances of the two wavelengths differ is displayed two-dimensionally.

Abstract: There are disclosed a nonlinear optical crystal 1 which can generate a THz wave by a parametric effect; a pump light incidence apparatus 12 for allowing a pump light 2 to be incident upon the nonlinear optical crystal; and a seed light injection apparatus 14 for injecting a seed light 5 having a variable frequency in a generation direction of an idler light 3 generated by the pump light. The seed light injection apparatus 14 comprises angle dispersion compensation means 16 set so that an incidence angle &thgr;IN of the seed light upon the nonlinear optical crystal 1 substantially equals to a desired phase matching condition regardless of a wavelength.

Abstract: A THz-wave generator according to the present invention includes a nonlinear optical crystal 1 capable of parametric generation, a first laser device 12 for injecting a single-frequency first laser beam 7 as a pump wave into the nonlinear optical crystal, and a second laser device 14 for injecting a different single-frequency second laser beam 8 to thereby injection-seed a second laser beam 8 in a direction in which an idler wave is generated by the pump wave. By this configuration, it is possible, in generation of a THz-wave by use of the parametric effect in the nonlinear optical crystal under a non-collinear phase matching condition, to greatly increase an power of the THz-wave, to narrow its spectrum width, to make variable the wavelength of a generated THz-wave, and to hold its generation direction almost constant.