Abstract: An LED filament includes an underlying layer exhibiting a first appearance at a first temperature, and an over-coated layer comprising a thermochromic material that exhibits at the first temperature, a preselected appearance other than the first appearance, and at a second temperature, a transparent or translucent appearance.

Abstract: A presence sensing method for a light comprises detecting a presence of a user by a sensing module having a first sensitivity while the light is off; turning on the light when identifying the presence of the user and keeping the light on for a delay time period which has a preset length; increasing a sensitivity of the sensing module to a second sensitivity after turning on the light; detecting actions of the user by the sensing module having the second sensitivity while the light is on; determining a length of a next delay time period based on the actions of the user during the previous delay time period immediately prior to the next delay time period; and keeping the light on for the next delay time period.

Abstract: The present invention discloses a lamp, comprising: an optical cover; a cap for connecting to electrical power; a tubular housing comprising an upper end connected to the optical cover hermetically, a lower end connected to the cap, and at least one vent opening located at a lower portion of the tubular housing; an air flow path inside the tubular housing for communicating an inner surface of the optical cover and the at least one vent opening; and a light source module and a driving module connected to the light source module inside the tubular housing. The present invention also discloses a lighting fixture comprising the above lamp and a lamp holder. The lamp and lighting fixture of the present invention are water resistant. When the gas inside the lamp causes the internal pressure to change due to expanding with heat and contracting with cold, the hermetically connected portions of the lamp are not easy to be damaged.

Abstract: An overcoated LED filament includes an LED filament comprising one or more LED dies coated with an underlying layer of a phosphor material exhibiting a colored appearance, and an over-coated layer comprising a resinous material loaded with a scattering agent that causes the LED filament to appear white.