Abstract: A hearing protection device includes: a sub-band splitting module configured to divide a first microphone input signal into sub-band signals having a first sub-band signal and a second sub-band signal; an estimator module configured to estimate signal strength parameters of respective sub-band signals, the signal strength parameters having a first signal strength parameter of the first sub-band signal, and a second signal strength parameter of the second sub-band signal; a multiband limiter; and a limiter controller; wherein the limiter controller is configured to determine gain reductions for the sub-band signals of the first microphone input signal, the gain reductions having a first gain reduction and a second gain reduction, and wherein the limiter controller is configured to control the multiband limiter to apply the second gain reduction to the second sub-band signal, wherein the second gain reduction for the second sub-band signal is based on the first signal strength parameter.

Abstract: A hearing protection device includes: a sub-band splitting module configured to divide a first microphone input signal into sub-band signals having a first sub-band signal and a second sub-band signal; an estimator module configured to estimate signal strength parameters of respective sub-band signals, the signal strength parameters having a first signal strength parameter of the first sub-band signal, and a second signal strength parameter of the second sub-band signal; a multiband limiter; and a limiter controller; wherein the limiter controller is configured to determine gain reductions for the sub-band signals of the first microphone input signal, the gain reductions having a first gain reduction and a second gain reduction, and wherein the limiter controller is configured to control the multiband limiter to apply the second gain reduction to the second sub-band signal, wherein the second gain reduction for the second sub-band signal is based on the first signal strength parameter.

Abstract: A zoom lens comprising, from the object side to the image side, a front lens group (72), a controllable lens group, and a rear lens group (74), the controllable lens group comprising a voltage-controlled electrowetting device, which device contains a first fluid (A) and a second fluid (B) having different refractive indices, with at least two first fluid-second fluid interfaces (40,42). The curvatures, and thus the lens power, of these interfaces can be changed independently by supplying a voltage (V1, V2) to electrodes (22,32) of the device, so that no mechanical movement of lens elements is needed.

Abstract: A switchable optical element is described, along with a method of manufacturing such an element. The switchable optical element (1) comprises a fluid chamber (2) including immiscible first and second bodies of fluid (20, 22) disposed relative to one another along an optical axis (A) of the element (1). The second body of fluid (22) is movable in a direction away from the optical axis (A) by electro-wetting action, giving the switchable optical element (1) a changeable transmissivity along the optical axis (A). The switchable optical element (1) is suitable for use as an optical attenuator, e.g. a shutter, filter or diaphragm, and can be conveniently used in place of mechanical alternatives in applications such as cameras, laser resonant cavities, projectors and devices for scanning optical record carriers.

Abstract: A variable focus lens comprising a first fluid (A) and a second, non-miscible, fluid (B) in contact over a meniscus. A first electrode (2) separated from the fluid bodies by a fluid contact layer (10), and a second electrode (12) in contact with the first fluid to cause an electrowetting effect whereby the shape of the meniscus is altered. The fluid contact layer has a substantially cylindrical inner wall.