A light emitting diode (LED) tube lamp configured to receive an external driving signal includes an LED module for emitting light, the LED module comprising an LED unit comprising an LED; a rectifying circuit for rectifying the external driving signal to produce a rectified signal, the rectifying circuit having a first output terminal and a second output terminal for outputting the rectified signal; a filtering circuit connected to the LED module, and configured to provide a filtered signal for the LED unit; and a protection circuit for providing protection for the LED tube lamp. The protection circuit includes a voltage divider comprising two elements connected in series between the first and second output terminals of the rectifying circuit, for producing a signal at a connection node between the two elements; and a control circuit coupled to the connection node between the two elements, for receiving, and detecting a state of, the signal at the connection node. The control circuit includes or is coupled to a switching circuit coupled to the rectifying circuit, and the switching circuit is configured to be triggered on or off by the detected state, upon the external driving signal being input to the LED tube lamp, to allow discontinuous current to flow through the LED unit.

A system and method of converting a light fixture from a conventional light fixture to an LED light fixture. Originally, the light fixture has a troffer, a ballast unit, and bulb receptacles. The conversion is accomplished by mounting a panel over the face of the troffer that obscures the ballast unit and bulb receptacles. LED light strips are mounted to the panel. Likewise, an LED power supply is mounted to the panel. The panel is attached to the troffer with a hinge connection. In this manner, the panel can be rotated away from the troffer for easy access.

A light fixture comprises a fixture body, at least one lamp mounted to the fixture body for emitting a light beam, at least one speaker device and/or at least one sound detection device and/or at least one image capturing device integrally mounted to the fixture body. The speaker device provides for emitting sound. The sound detection device provides for detecting ambient sound. The Image capturing device provides for capturing an image. A controller is in operative communication with the at least one lamp, to the at least one speaker and/or to the at least one sound detection and/or at least one image capturing device for control thereof. A system for controlling the light emitted by these light fixtures comprises a master controller for receiving information from the controller and for transmitting control signals thereto.

A light fixture comprises a fixture body, at least one lamp mounted to the fixture body for emitting a light beam, at least one speaker device and/or at least one sound detection device and/or at least one image capturing device integrally mounted to the fixture body. The speaker device provides for emitting sound. The sound detection device provides for detecting ambient sound. The Image capturing device provides for capturing an image. A controller is in operative communication with the at least one lamp, to the at least one speaker and/or to the at least one sound detection and/or at least one image capturing device for control thereof. A system for controlling the light emitted by these light fixtures comprises a master controller for receiving information from the controller and for transmitting control signals thereto.

A linear light-emitting diode (LED)-based solid-state lamp comprises an LED driving circuit, LED arrays, a rectifier configured to convert an input AC voltage into a DC voltage, and an electric arc detection and current control module. The electric arc detection and current control module comprises a first derivative circuit configured to detect voltage variations from the DC voltage provided by the rectifier. The DC voltage varies drastically when an electric arc occurs while maintaining intact when the input AC voltage is not affected by the electric arc. The first derivative circuit takes a first-derivative of the voltage variations, coupling to a comparator circuit to determine if the electric arc occurs. When the electric arc is detected, the electric arc detection and current control module shuts off a current return from the LED arrays to reach the rectifier, hence preventing the electric arc from occurring during relamping or operating.

An elongated heatsink structure retaining single and/or bi-directional light sources that receive variable power input(s) through at least one endcap coupled to the elongated heatsink structure.

An elongated heatsink structure retaining single and/or bi-directional light sources that receive variable power input(s) through at least one endcap coupled to the elongated heatsink structure.

Retrofit kits for retrofitting LED light engines into existing light fixture housings. The retrofit kit includes a hook bracket that may be mounted in the housing and from which an end of the LED light engine can be suspended so as to permit an installer to electrically connect the LED light engine. The retrofit kit also includes a mounting bracket to secure the free end of the LED light engine into the housing after the LED light engine has been rotated upwardly into the housing from the hanging position.

Light emitting diode (LED) light tubes having rotatable end cap assemblies are described. The LED light tubes include a hollow tube and a circuit board with LED chips thereon. The end cap assemblies are provided on either end of the tube. Each end cap assembly includes a socket cap, a plug having a plug body and at least one connector, and an end cap body, one end of which engages one of the ends of the hollow tube. A cam locking mount that is positioned within the plug body and on the opposite side has projections to be positioned in the bore of the end cap body. A rotation cam is seated in the cam locking mount and provides for controlled rotation of the LED tube relative to the end caps. Methods of installing the LED light tubes in new installations and retrofit installations and for use in sign assemblies are also described.

Light emitting diode (LED) light tubes having rotatable end cap assemblies are described. The LED light tubes include a hollow tube and a circuit board with LED chips thereon. The end cap assemblies are provided on either end of the tube. Each end cap assembly includes a socket cap, a plug having a plug body and at least one connector, and an end cap body, one end of which engages one of the ends of the hollow tube. A cam locking mount that is positioned within the plug body and on the opposite side has projections to be positioned in the bore of the end cap body. A rotation cam is seated in the cam locking mount and provides for controlled rotation of the LED tube relative to the end caps. Methods of installing the LED light tubes in new installations and retrofit installations and for use in sign assemblies are also described.