A beverage dispenser ingredient level detection system is disclosed. The system may include a container with a wall, a canister, a capsule, an infrared emitter, and an infrared receiver. The canister may be disposed within the container at a first distance from the wall and may be configured to hold a beverage ingredient. The capsule may be disposed on an interior surface of the wall. The infrared emitter and the infrared receiver may be disposed within the capsule and the infrared receiver may be configured to transmit infrared light rays and the infrared receiver may be configured to detect infrared light rays reflected by the beverage ingredient in the canister to determine whether a pre-determined amount of the beverage ingredient is within the canister. The capsule may absorb infrared light rays that are not indicative of whether the pre-determined amount of the beverage ingredient is within the canister.

A system and a method include a container configured to retain one or more liquids. A liquid level sensor is disposed within the container. The liquid level sensor includes a plurality of sensing elements configured to sense a level of the one or more liquids within the container. In at least one example, the sensing elements are optical fibers.

An aircraft is described and includes an aircraft body, a gearbox housing containing a lubricant, and a remote gearbox lubricant level gauging (RGLLG) system including a light source that when activated illuminates an interior of the gearbox housing; at least one light tube for transmitting light from inside the gearbox housing to an observer end of the RGLLG system, and at least one indicator at the observer end of for indicating a level of the lubricant contained within the gearbox based on the light transmitted via the at least one light tube.

A fluid level sensing system includes a mounting strip and fluid sensing nodes coupled to the mounting strip. Each fluid sensing node is switchable between a fluid present state and a fluid absent state. Each fluid sensing node includes a prism, a photoemitter and a photoreceptor. The photoemitter and photoreceptor are interposed between the prism and the mounting strip. In the absence of fluid around the prism, the photoreceptor receives greater than a threshold amount of light from the photoemitter internally reflected by the prism to switch the fluid sensing node to the fluid absent state. When the prism is covered in fluid, the photoreceptor receives less than the threshold amount of light from the photoemitter to switch the fluid sensing node to the fluid present state. A processor determines a fluid level based on the fluid detection states of the fluid sensing nodes.

A sensor apparatus for determining and/or monitoring a process variable of a medium in a containment includes: a crystal body including at least one defect; a magnetic field system for producing a magnetic field in the region of the crystal body and in the region of the medium within the containment, wherein the crystal body and the magnetic field system are arrangeable from the outside at a wall of the containment; a detection unit for detecting a magnetic field-dependent, fluorescent signal from the crystal body, wherein the detection unit has an excitation unit for optical exciting of the defect and a detector for detecting the fluorescent signal; and an evaluation unit for ascertaining at least one piece of information concerning the process variable based on the fluorescent signal.

A system and a method include a container configured to retain one or more liquids. A liquid level sensor is disposed within the container. The liquid level sensor includes a plurality of sensing elements configured to sense a level of the one or more liquids within the container. In at least one example, the sensing elements are optical fibers.