An optical fiber holding device having an optical fiber having a diameter held therein, the optical fiber holding device comprising: a base plate (30, 40a, 40b) with a first spiral channel (32, 42a) in an upper surface thereof holding the optical fiber, the channel (32, 42) comprising: a plurality of turnings for holding the optical fiber in a spiral pattern; a radially inner sidewall and a radially outer sidewall separated by a first channel width; and a substantially flat bottom between the inner and the outer sidewalls, wherein, when viewed in cross section: the outer sidewall of the first spiral channel (32, 42a) is incut to retain the optical fibre in the first spiral channel (32, 42a), the optical fiber pressing itself against the outer sidewall of the first spiral channel (32, 42a), or the outer sidewall of the first spiral channel (32, 42a) is semi-circular and sized to conform to and tightly accommodate the shape of the optical fiber as it presses against the outer sidewall, wherein, for both outer sidewall shapes, the first channel width is larger than the diameter of the optical fiber; the device being characterised in that the minimum radius of curvature of the first spiral channel (32, 42a) is at least 2 cm, the first channel comprising a first location for the optical fibre to enter the first spiral channel, the first channel comprising a second location for the optical fibre to exit the first channel, and the inner sidewall of the first spiral channel is orthogonal to the flat bottom of the first spiral channel. a base plate (30, 40a, 40b) with a first spiral channel (32, 42a) in an upper surface thereof holding the optical fiber, the channel (32, 42) comprising: a plurality of turnings for holding the optical fiber in a spiral pattern; a radially inner sidewall and a radially outer sidewall separated by a first channel width; and a substantially flat bottom between the inner and the outer sidewalls, wherein, a plurality of turnings for holding the optical fiber in a spiral pattern; a radially inner sidewall and a radially outer sidewall separated by a first channel width; and a substantially flat bottom between the inner and the outer sidewalls, wherein, when viewed in cross section: the outer sidewall of the first spiral channel (32, 42a) is incut to retain the optical fibre in the first spiral channel (32, 42a), the optical fiber pressing itself against the outer sidewall of the first spiral channel (32, 42a), or the outer sidewall of the first spiral channel (32, 42a) is semi-circular and sized to conform to and tightly accommodate the shape of the optical fiber as it presses against the outer sidewall, wherein, for both outer sidewall shapes, the first channel width is larger than the diameter of the optical fiber; the device being characterised in that the minimum radius of curvature of the first spiral channel (32, 42a) is at least 2 cm, the first channel comprising a first location for the optical fibre to enter the first spiral channel, the first channel comprising a second location for the optical fibre to exit the first channel, and the inner sidewall of the first spiral channel is orthogonal to the flat bottom of the first spiral channel. the outer sidewall of the first spiral channel (32, 42a) is incut to retain the optical fibre in the first spiral channel (32, 42a), the optical fiber pressing itself against the outer sidewall of the first spiral channel (32, 42a), or the outer sidewall of the first spiral channel (32, 42a) is semi-circular and sized to conform to and tightly accommodate the shape of the optical fiber as it presses against the outer sidewall, wherein, for both outer sidewall shapes, the first channel width is larger than the diameter of the optical fiber; the device being characterised in that the minimum radius of curvature of the first spiral channel (32, 42a) is at least 2 cm, the first channel comprising a first location for the optical fibre to enter the first spiral channel, the first channel comprising a second location for the optical fibre to exit the first channel, and the inner sidewall of the first spiral channel is orthogonal to the flat bottom of the first spiral channel.