Abstract: There is provided a foldable electronic apparatus in which first and second casings are pivotally mounted by a bearing portion so as to be freely rotatable and these casings are automatically opened until a predetermined opening angle and then further manually opened. In the electronic apparatus of the present invention, the first and second casings (1), (2) are freely rotatably connected to each other (pivotally mounted) through a bearing portion (3). An opening/closing device (4) for automatically opening the first and second casings (1), (2) until a predetermined opening angle by operating a push button (49) is secured to the bearing portion. The opening/closing device (4) includes a mechanism for opening the casings until a larger opening angle exceeding the predetermined opening angle, and the first and second casings (1), (2) can be manually opened till a larger opening angle.

Abstract: A folding device contains a stationary part, a movable part disposed to be rotatable in flip-up (unfolding) and flip-down (folding) directions, a force-applying section disposed between the two parts, which urges the movable part in either direction according to a state of the movable part, a reversing section for allowing the force-applying section to change a direction of urging of the movable part into the flip-up (unfolding) direction when the movable part is in a folded state, and an actuator for operating the reversing section. Pressing the actuator being in the folded state allows the reversing section to switch the direction of urging of the movable part into flip-up (unfolding) direction. In the electronic equipment of the present invention, the stationary and the movable housings are connected to the stationary and the movable parts of the folding device, respectively.

Abstract: Inclined plane is provided at the tip of rotor cam. On the other hand, inclined planes are also provided in specific positions of stator cam. Because of this structure, in the specific positions, the inclined planes are in resilient contact with each other. Thus, the load is increased only in the specific positions without an increase in the load of spring. This structure can provide an opening and closing device capable of securely holding only desired positions without affecting the feel of opening and closing operation of the entire device, and electronic equipment using the device.

Abstract: The folding device contains a stationary part; a movable part disposed rotatable in flip-up and flip-down directions; a force-applying section disposed between the two parts, which urges the movable part in either direction according to the state of the movable part; a reversing section for allowing the force-applying section to change direction of urging the movable part into the flip-up direction when the movable part has a folded state; and a actuator for operating the reversing section. Pressing the actuator being in the folded state allows the reversing section to switch direction of urging the movable part into flip-up direction. In the electronic equipment of the present invention, the stationary and the movable housings are connected to the stationary and the movable parts of the folding device, respectively. The structures can provide a folding device equipped with a simple one-hand flipping-up, and electronic equipment using the device.

Abstract: A light source emits light having two components which ave slightly-different frequencies and which have different planes of polarization. The emitted light is separated into first, second, and third parts travelling along different paths respectively. First, second, and third reference gratings diffract the first, second, and third light parts respectively. First, second, and third illumination optical systems selectively transmit the diffracted first, second, and third light parts respectively. First, second, and third mark gratings having predetermined orientations are formed on a mask and are illuminated with the first, second, and third light parts coming from the first, second, and third illumination systems respectively. Similarly, first, second, and third mark gratings are formed on a wafer and are illuminated with the first, second, and third light parts coming from the first, second, and third illumination systems respectively.

Abstract: A system for controlling the relation in position between a photomask and a wafer for use in manufacturing apparatus of a highly integrated circuit such as large scale integration (LSI). The position control system includes a coherent light source for generating two light beams which are different in frequency and polarizing direction from each other. The light beams from the coherent light source is introduced into a first diffraction grating and the diffracted light from the first diffraction grating selectively pass through a telecentric lens system and are led to second and third diffraction gratings respectively disposed on the photomask and the wafer. Light beat signals are obtained in correspondance with the diffracted light from the second and third difraction gratings and the position relation between the photomask and wafer is controlled on the basis of the phase difference between the obtained light beat signals which corresponds to the position difference between the photomask and the wafer.

Abstract: Processing of plural works can be made simultaneously by using divided laser beams which is issued from one large Co.sub.2 laser beam source, the dividing being made by one or more rotary chopper mirror(s) comprising reflecting parts and light passing parts, and its ration and pulsive start and stop of laser oscillation are controlled in interrelated manner and by controlling the duty time of the laser oscillation in PWM manner. The distribution of powers of the laser beams divided by the rotary chopper mirrors is desirably selectable, thereby enabling simultaneous processing of plural works under the different processing conditions.