Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Denki K.k.

Yasushi Minamitani

Hajime Nakatani

Atsushi Sugitatsu

Hitoshi Wakata

Akihiko Iwata

Takashi Kumagai

Tomohiro Sasagawa

Akihiro Suzuki

Nobuyuki Zumoto

Kenyu Haruta

Tadao Minagawa

Toshinori Yagi

Masao Izumo

Yoshifumi Matsushita

An optical processing apparatus for processing optically a workpiece (7) by using a light beam (B). The apparatus is capable of automatically adjusting a imaging magnification to a predetermined value and at the same time maintaining constant a imaging magnification regardless of exchange of masks (3; 100) and workpieces (7) and for ensuring an extended use life of a mask with satisfactory mask function. The apparatus includes a light source system (1) for generating a light beam (B) for illuminating a mask (3; 100) having a predetermined pattern, a imaging lens (5) for copying a pattern image of the mask (3; 100) onto a workpiece (7), a mask moving mechanism (4) for moving the mask in a direction perpendicular to an optical axis (L) of the imaging lens (5), a workpiece moving mechanism for moving the workpiece in a direction perpendicular to the optical axis (L) of the imaging lens (5), a imaging magnification changing mechanism for changing inter-mask/lens/workpiece distance between the mask, the imaging lens and the workpiece, and a central control unit (9) which is comprised of an actual imaging magnification arithmetic module (91) for determining an actual imaging magnification value (M') in terms of a ratio between the copied pattern image and a predetermined pattern, a magnification decision module (92) for making decision whether or not a difference between the actual imaging magnification value and a desired imaging magnification value is smaller than a permissible value, an optical-axis displacement control module (93) responsive to indication that the difference exceeds a permissible value (.delta.) to thereby arithmetically determine on the basis of the actual and desired imaging magnification values the inter-mask/lens/workpiece distance at which the actual imaging magnification value (M') becomes equal to the desired imaging magnification value (M) for controlling thereby the imaging magnification changing mechanism so that the inter-mask/lens/workpiece distance coincides with the arithmetically determined distance, and a displacement control module for controlling the mask moving mechanism and the workpiece moving mechanism.

Optical processing method and apparatus for carrying out the same

A discharge excitation type pulse laser apparatus includes main discharge electrodes and and an auxiliary discharge electrode. In order to make a voltage pulse applied to the auxiliary discharge electrode rise up steeply without incurring any appreciable time lag, a reactor connected in series to a first charging capacitor is constituted by a first saturable reactor 19 with a second saturable reactor being additionally inserted in series to a second charging capacitor. After stray inductance and resistance components of a switch become minimum, inductance of the saturable reactor is first decreased, which is then followed by decreasing of inductance of the first saturable reactor. Degree of steepness of the voltage rise-up for corona and main discharges can set at high values, respectively, whereby preionization is accelerated to allow the main discharge to occur uniformly. The energy injected into the main discharge is increased. Laser output power and oscillation efficiency are enhanced.

Discharge excitation type pulse laser apparatus

Pulse laser apparatus

A discharge-excited laser apparatus includes a pair of discharge electrodes extending in a direction of an optical axis; a plurality of charging capacitors charged by a power source; a plurality of peaking capacitors arranged in parallel in a longitudinal direction of the discharge electrodes and receiving energy accumulated in the charging capacitors; and a plurality of semiconductor switches arranged with conductive plates in the longitudinal direction of the discharge electrodes and connected in series and in parallel to the peaking capacitors. The construction of the semiconductor switches enables uniform shift of the energy in the charging capacitors to the peaking capacitors and reduction of inductance of a loop for capacity shifting.

Discharge-excited laser apparatus

A wavelength monitor/stabilizer for narrowly controlling the bandwidth of laser; the monitor/stabilizer uses parameters Q, F or G derived by measuring diameters of interference fringes given by the beam of the wavelength-controlled narrow bandwidth laser e.g. excimer laser and those given by the reference light e.g. of a mercury lamp. The controlling is made by controlling the parameter to be in a predetermined range. An image sensing unit for detecting the interference fringes are splitted into plural image sensors with adjustable distance for enabling more rapid measurement by skipping the in-between part.

Wavelength stabilizer for narrow bandwidth laser

Growing community of inventors

Amagasaki, Japan

Yasushi Minamitani