Hitachi, Ltd.

Masayoshi Kameyama

Minoru Maeda

Katsuyuki Imoto

Shigeru Oho

Seiji Kashioka

Masakazu Ejiri

Hiroshi Araki

Yasushi Ikuta

Takafumi Miyatake

Haruo Yoda

Kazuo Ichino

Takahumi Miyatake

Hiroshi Horiguchi

An optical star coupler having a biconically tapered optical star coupler suspensively inserted in a protection tube and the method for manufacturing the same are disclosed, and the manufacturing method is that an optical fiber bundle is inserted into a protection tube such as hollow glass tube, then the optical fiber bundle is twisted and pulled while it is indirectly heated through the protection tube, thereby to form a twisting, fusing and pulling portion, and both ends of the protection tube are sealed with an adhesive agent to fix the optical fiber bundle to the protection tube. This optical star coupler can be constructed so as to be connected in tandem without any splicing. The optical star coupler of the present invention, naturally in the case of an optical star coupler using multi-mode optical fiber, particularly in the case of one equally divided optical star coupler using single-mode optical fiber, also provides low insertion loss, less power deviation and low manufacturing cost.

Optical star coupler and method of manufacturing the same

An optical star coupler having a biconically tapered optical star coupler inserted and suspended in a protection tube and the method for manufacturing the same are disclosed. The manufacturing method provides that an optical fiber bundle is inserted into a protection tube such as hollow glass tube, then the optical fiber bundle is twisted and pulled while it is indirectly heated through the protection tube, thereby forming a twisting, fusing and pulling portion. Both ends of the protection tube are then sealed with an adhesive agent to fix the optical fiber bundle to the protection tube. This optical star coupler can be constructed so as to be connected in tandem without any splicing. The optical star coupler of the present invention, in the case of an optical star coupler using multi-mode optical fibers, and particularly in the case of one equally divided optical star coupler using single-mode optical fiber, also provides low insertion loss, less power deviation and low manufacturing costs.

Optical star coupler and method for manufacturing the same

This invention relates to a driving signal control circuit, in which at least four detecting points (or detectors) are arranged for detecting the position of the working table, which is repeatedly reciprocated between the detecting points. The control circuit includes a clock generator for generating a clock signal in accordance with a start signal, a gate circuit operative in response to detecting signals derived from the detectors when the working table has reached the detecting points, for selectively applying the clock signal as an Up output signal or a Down output signal and for providing a switching signal, a counter circuit for adding the Up output signal or for subtracting the Down output signal, a digital-to-analog converter for converting a digital output signal of the counter circuit into an analog signal, and a switching circuit operative for generating a driving signal with negative polarity or positive polarity in accordance with the switching signal and corresponding to the analog signal in value, whereby the working table can be smoothly moved by the driving signal without generating mechanical vibration in the working table.

Driving signal control circuit

A group control system comprises multi-combinations of image pick-up devices and an automatic assembly apparatus controlled by information from the image pick-up devices. A computer responds to demands from the image pick-up devices and the automatic assembly apparatus which independently operate with the computer. A plurality of visual information processing apparatus are provided between the interface of the computer and the image pick-up devices, for processing information therefrom, and a pulse generator is coupled to the image pick-up devices and the visual information processing apparatus, for controlling the operations thereof. The image pick-up devices are grouped into a plurality of groups each of which is coupled to each visual information processing apparatus. The plurality of visual information processing apparatuses are timed by different timing pulses from the pulse generator, whereby processing of the information from a great number of the image pick-up devices is efficiently performed by the computer.

Group control system for visual information processing

A feature extraction system comprises first and second memory circuits and a control circuit for controlling a storing period of time when signals are stored in the first memory circuit. The first and the second memory circuits comprise capacitor memory circuits, the time constant of the second memory circuit being larger than that of the first memory circuit. First and second comparators are coupled to the first and the second memory circuit, respectively. Signals supplied to the first memory circuit are compared with the contents thereof by the first comparator, so that the maximum signal thereof within a predetermined period of time controlled by the control circuit is stored in the first memory circuit. After the predetermined period of time, the contents of the first memory circuit are supplied to the second memory circuit and then the first memory circuit operates to store the maximum signal of the signals supplied to the first memory circuit within a next predetermined period of time. Signals from the first memory circuit are compared with the contents thereof by the second comparator in order to extract the maximum signal of the signals from the first memory circuit, which is stored in the second memory circuit, whereby the maximum signal in the signals supplied to the first memory circuit can be accurately extracted.

Growing community of inventors

Sagamihara, Japan

Masayoshi Kameyama