An image forming apparatus includes a container and a detecting portion. The detecting portion includes a light emitting element, a light receiving element, and a light guiding portion. The light guiding portion includes first to fourth projected portions. An upper surface of the second projected portion is positioned above a first virtual rectilinear line along an upper surface of the first projected portion in a case where an upper surface of the second projected portion is viewed in a direction crossing both a first direction and a direction of gravitation. An upper surface of the third projected portion is positioned above a second virtual rectilinear line along an upper surface of the fourth projected portion as viewed in a direction crossing a second direction and the direction of gravitation.

An aircraft fuel tank, which includes a water sensor, arranged at the bottom of the tank and connected to a calculation and processing mechanism in order to receive a presence of water signal sent by the sensor, and to return information regarding the need, or not, to perform a fuel tank drainage operation.

A trap bowl is provided to accumulate liquid droplets from a filter, as a liquid content. The trap bowl includes a transparent vertical prism. The transparent vertical prism includes a face that forms a vertical transparent surface facing against a content of the section. The face can provide a first angle of total reflection when content of the section is a type of gas, and a second angle of total reflection when the content of the section is the liquid content. A light source may emit a light beam incident on the face at an angle of incidence. The angle of incidence results in reflection of the light beam, striking the light receiver, when the face has the first angle of total reflection, and results in refraction of the light beam, missing the light receiver, when the face has the second angle of total reflection.

A detecting apparatus includes a container, and a detecting device including a transmitting module and a receiving module. The transmitting module includes a light-emitting element provided at a first point of the container and operable to transmit a photo signal to propagate toward the container along an optical path. The receiving module includes a light-receiving element provided at a second point of the container and configured to receive the photo signal transmitted through the container. The receiving module is operable to determine whether a substance is present within the container based on receipt of the photo signal. An imaginary tangent plane tangent to the first point is not parallel to an imaginary tangent plane tangent to the second point.

A liquid cartridge includes a first surface, a second surface spaced apart from the first surface, and a third surface extending between the first surface and the second surface, with a liquid outlet through the first surface. A circuit board is mounted on the third surface. A locking mechanism includes a locking surface that extends above the third surface, and a liquid detection mechanism includes a light access portion. The light access portion is disposed between the circuit board and the locking surface, and the circuit board is disposed between the first surface and the light access portion.

A liquid reservoir for a humidifier containing a base, a top portion opposite the base, a side wall, and a liquid presence indicator. The side wall contains a lower side wall portion adjacent to the base, and an upper side wall portion adjacent to the top portion. The liquid presence indicator interacts with the humidifier to detect the presence of liquid in the liquid reservoir. A humidifier, and/or a medical device may contain the liquid reservoir, and a method may employ the humidifier and/or medical device.

A carbon dioxide absorber (1) and a closed-circuit breathing apparatus (2) with the carbon dioxide absorber are based on the carbon dioxide absorber having an inlet (3) and an outlet (4) gas-tight connectable by a flow duct (5), in which a material (6) is arranged, which absorbs some carbon dioxide contained in the breathing gas stream sent through the material. The flow duct (5) is enclosed in some areas by a housing (7), in which a window element (8) is arranged. A display element (9) arranged movably in the flow duct (5) is visible through the window element from outside of the housing and/or through which window element the radiation reflected by the display element (9) exits to the outside. A distance between the window element (8) and the display element (9) varies as a function of the quantity of carbon dioxide-absorbing material arranged in the flow duct (5).

A method of operating an electro-optic sensor includes disposing at least a portion of the electro-optic sensor in a liquid chamber, providing light from a light source of the electro-optic sensor at a first intensity, driving a light detector of the electro-optic sensor at a first sensitivity level, receiving, via the light detector, a first amount of light from the light source; determining whether liquid is present in the liquid chamber according to the first amount of light, providing light from the light source at a second intensity, driving the light detector at a second sensitivity level, receiving, via the light detector, a second amount of light from the light source, and/or confirming whether liquid is present in the liquid chamber according to the second amount of light. The first sensitivity level may be different from the second sensitivity level.

The present disclosure provides an electro-optic sensor that performs well in a wide range of temperatures. The sensors of the present disclosure can be used in high temperature applications. In some embodiments, the sensor can detect the presence or absence of fluid as well as measure temperature.

A trap bowl is provided to accumulate liquid droplets from a filter, as a liquid content. The trap bowl includes a transparent vertical prism. The transparent vertical prism includes a face that forms a vertical transparent surface facing against a content of the section. The face can provide a first angle of total reflection when content of the section is a type of gas, and a second angle of total reflection when the content of the section is the liquid content. A light source may emit a light beam incident on the face at an angle of incidence. The angle of incidence results in reflection of the light beam, striking the light receiver, when the face has the first angle of total reflection, and results in refraction of the light beam, missing the light receiver, when the face has the second angle of total reflection.