Kotura, Inc.

Other

Bookham Technology Limited

George Frederick Hopper

Andrew Alan House

Adrian Petru Vonsovici

Andrew Peter Knights

Dominic Joseph Brady

Takashi Sato

Richard J Penneck

Ian Edward Day

Masanori Furuta

Shigefumi Torii

The sensor includes an optical waveguide defined in a light-transmitting medium. The waveguide includes a sensing portion and an non-sensing portion. The light-transmitting medium included in the sensing portion has defects that provide the light-transmitting medium with a deep band gap level between a valence band of the light-transmitting medium and a conduction band of the light-transmitting medium. The deep band gap level is configured such that the waveguide guiding light signals through the light-transmitting medium in the sensing portion causes free carriers to be generated in the light-transmitting medium. A detector is configured to detect the free carriers in the sensing region of the waveguide.

In-line light sensor

An integrated optical waveguide () having an in-line light sensor () integrally formed therewith for tapping off a small proportion of the signal transmitted along the waveguide (). A first part (A) of the waveguide leads to a photodiode portion () and a second part (B) of the waveguide leads away from the photodiode portion (), the photodiode portion () comprising one or more regions () of light absorbing material within the waveguide () arranged to absorb a minor proportion of light transmitted along the waveguide () and thereby to generate free charge carriers within the waveguide (). Deep band gap levels () are introduced into photodiode portion by ion implantation to enable it to absorb selected wavelengths. The free charge carriers are detected by a p-i-n diode formed across the waveguide (). Wavelength selective reflectors () may be provided either side of the photodiode portion () so light passes repeatedly through the photodiode portion ().

An isolation device that can be used for providing optical and electrical isolation between areas of an integrated chip. The isolation device includes three doped elongate regions which form diodes which can be connected in series. The isolation device can be used in optical devices or optical attenuators.

Isolation device

The present invention relates to an over-discharge preventing circuit, especially an over-discharge over-current preventing circuit, and more specifically relates to an over-discharge over-current preventing circuit comprising an over-discharge preventing circuit having a FET and an over-current preventing circuit for protecting the FET. The invention includes a primary or secondary battery containing such a circuit, and a battery pack containing such a circuit. The batteries comprising an over-discharge over-current preventing circuit according to the present invention have (1) an electrolyte, (2) a pair of electrode members forming a negative electrode member and a positive electrode member which electrically contact the electrolyte, (3) a pair of external connection terminals respectively electrically connected to corresponding electrode members and (4) a PTC element and FET with a source terminal and drain terminal serially connected between one of the electrode members and the corresponding external connection terminal, the gate terminal being connected to the other electrode member. The FET prevents over-discharge by stopping the supply of current to the external connection terminal when the voltage between the electrode members becomes lower than a predetermined value. The PTC element prevents over-current by stopping the supply of current to the external terminal when the current between the electrode members exceeds a predetermined value, thereby also protecting the FET from being destroyed by such an over-current.

Battery over-discharge protection

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Maidenhead, United Kingdom

George Frederick Hopper