Abstract: A sensor for measuring flow speed of a fluid, comprising: a light-absorbing optical fiber having a fiber Bragg grating inscribed in the fiber; wherein light is emitted into the light-absorbing optical fiber to heat the optical fiber and the fiber Bragg grating, and when the fluid passes over the sensor, the flow speed of the fluid is determined by the rate of heat loss from the sensor, and the temperature of the sensor is determined from the wavelength shift of the central wavelength of the fiber Bragg grating.

Abstract: A sensor for measuring flow speed of a fluid, comprising: a light-absorbing optical fiber having a fiber Bragg grating inscribed in the fiber; wherein light is emitted into the light-absorbing optical fiber to heat the optical fiber and the fiber Bragg grating, and when the fluid passes over the sensor, the flow speed of the fluid is determined by the rate of heat loss from the sensor, and the temperature of the sensor is determined from the wavelength shift of the central wavelength of the fiber Bragg grating.

Abstract: A pressure gauge includes a housing and a mechanical sensor placed in the housing for sensing change of the pressure. A characteristic of the sensor varies in correspondence to the change of the pressure. The gauge also includes an optical fiber, at least part of which is in the housing with a first end connected to the sensor such that a characteristic of the fiber varies in correspondence to the variance of the characteristic of the sensor, and an optical signal generator connected to a second end of the fiber for emitting an optical signal into the fiber. The second end of the fiber is distanced from the sensor, and the fiber generates at least a first reflected optical signal towards said second end, which first reflected optical signal contains information relating to the variance of the characteristic of the fiber.

Abstract: A pressure gauge includes a housing and a mechanical sensor placed in the housing for sensing change of the pressure. A characteristic of the sensor varies in correspondence to the change of the pressure. The gauge also includes an optical fiber, at least part of which is in the housing with a first end connected to the sensor such that a characteristic of the fiber varies in correspondence to the variance of the characteristic of the sensor, and an optical signal generator connected to a second end of the fiber for emitting an optical signal into the fiber. The second end of the fiber is distanced from the sensor, and the fiber generates at least a first reflected optical signal towards said second end, which first reflected optical signal contains information relating to the variance of the characteristic of the fiber.

Abstract: A microlens array includes short lengths of fibre held across an aperture in a rigid body. The fibres are conveniently short lengths cut from commercially available ultraviolet grade fused silica fibre that has had a normal outer protective coating removed. The microlens array is comparatively cheap to make and has particular application in producing long period gratings by exposing strands of silica fibre to UV radiation via the microlens array using a diffraction pattern produced by the microlens.