An air filter includes: a pleated filter material folded into a zig-zag form at folding lines along a first direction to have peak parts and valley parts arising alternately in a second direction perpendicular to the first direction, trapping fine particles in a gaseous matter flowing in a gas flow direction perpendicular to the first direction and the second direction; a filter frame being a rectangular filter frame including one pair of first frame materials facing each other in the second direction having end parts in the first direction, and one pair of second frame materials facing each other in the first direction having end parts in the second direction, opening in the gas flow direction and housing the pleated filter material, each of the first frame materials and each of the second frame materials being combined to provide an overlap part.

An air filter includes: a pleated filter material folded into a zig-zag form at folding lines along a first direction to have peak parts and valley parts arising alternately in a second direction perpendicular to the first direction, trapping fine particles in a gaseous matter flowing in a gas flow direction perpendicular to the first direction and the second direction; a filter frame being a rectangular filter frame including one pair of first frame materials facing each other in the second direction having end parts in the first direction, and one pair of second frame materials facing each other in the first direction having end parts in the second direction, opening in the gas flow direction and housing the pleated filter material, each of the first frame materials and each of the second frame materials being combined to provide an overlap part.

A powered room air purifier with a visual indicator of air quality, the visual indicator including: a reflector that defines a forwardly-open-ended reflecting cavity and that comprises at least one through-opening in a floor or ceiling of the reflector; at least one diffuser layer that covers the forward opening of the forward-open-ended reflecting cavity; and, at least one LED light source that is positioned within the at least one through-opening, the LED light source and the reflector being configured so that the LED light source is shielded from line-of-sight view along a forward-rearward axis of the powered room air purifier.

A powered room air purifier with a visual indicator of air quality, the visual indicator including: a reflector that defines a forwardly-open-ended reflecting cavity and that comprises at least one through-opening in a floor or ceiling of the reflector; at least one diffuser layer that covers the forward opening of the forward-open-ended reflecting cavity; and, at least one LED light source that is positioned within the at least one through-opening, the LED light source and the reflector being configured so that the LED light source is shielded from line-of-sight view along a forward-rearward axis of the powered room air purifier.

An energy-transmissible air filtration system having at least one mechanical filter and at least one electromagnetic energy source. The electromagnetic energy source generates an electromagnetic energy wave or force that traverses the at least one mechanical filter. This results in substantially simultaneous mechanical filtration and energy-based decontamination of an airstream. Other features of the embodiments are also shown.

An energy-transmissible air filtration system having at least one mechanical filter and at least one electromagnetic energy source. The electromagnetic energy source generates an electromagnetic energy wave or force that traverses the at least one mechanical filter. This results in substantially simultaneous mechanical filtration and energy-based decontamination of an airstream. Other features of the embodiments are also shown.

An air cleaner capable of removing bacteria and viruses. The air cleaner includes: a main body including a suction hole through which air is introduced and a discharge hole through which air is discharged; an ultraviolet (UV) irradiation device disposed between the suction hole and the discharge hole, and including a UV light emitting diode (LED) configured to transmit ultraviolet rays toward the discharge hole; a photocatalyst filter including a photocatalyst provided to generate active oxygen by reacting with the UV rays transmitted from the UV LED, and disposed between the UV irradiation device and the discharge hole; and a light blocking member disposed between the UV LED and the suction hole to prevent the UV rays transmitted from the UV LED from being emitted to an outside of the main body through the suction hole.

Air-cleaning control is performed in accordance with a situation of motion of a person and brightness in a room. An air-cleaning device (100) includes: a first determination unit (11) that determines, from a detection signal from a person detection sensor (31), whether a state of an air-cleaning target room is at least any of a state where a person is absent in the air-cleaning target room, a state where a person is present and a motion amount is small, and a state where a person is present and the motion amount is large; a second determination unit (12) that determines, from a detection signal from as illuminance sensor (32), whether the state of the air-cleaning target room is at least any of a state where it is bright inside the air-cleaning target room and a state where it is dark inside the air-cleaning target room; and an operation control unit (13) that controls an operation of an air-cleaning function by using determination results of the first determination unit (11) and the second determination unit (12).

A hybrid clean room system includes: a clean room which includes a plurality of side walls arranged in the vertical direction between a floor part and a ceiling part; a circulation part which is disposed outside of the clean room, and which forms a closed space along the upper plate with the other two facing side walls from among the plurality of side walls; an air pump disposed in the circulation part; a plurality of discharge ports, which are arranged on the other two facing side walls from among the plurality of side walls so as to supply, to the clean room, the air that is discharged from the air pump and passes through the circulation part; a suction part disposed at at least one of the plurality of side walls, and connected to the air pump.

A hybrid clean room system includes: a clean room which includes a plurality of side walls arranged in the vertical direction between a floor part and a ceiling part; a circulation part which is disposed outside of the clean room, and which forms a closed space along the upper plate with the other two facing side walls from among the plurality of side walls; an air pump disposed in the circulation part; a plurality of discharge ports, which are arranged on the other two facing side walls from among the plurality of side walls so as to supply, to the clean room, the air that is discharged from the air pump and passes through the circulation part; a suction part disposed at at least one of the plurality of side walls, and connected to the air pump.