A light projection device includes a tubular casing having a light-emitting part at one tube end; a light source configured with a light-emitting diode; and a light amount control mechanism positioned between the light source and the light-emitting part. The light amount control mechanism includes a rotating body, an operating part attached to the rotating body such as to allow for rotary operation of the rotating body from outside the casing, a variable resistor, and a link mechanism operably connecting the rotating body and the variable resistor such that a forward movement of the rotating body causes a movable part of the variable resistor to move in a direction in which the amount of current is increased and such that a backward movement of the rotating body causes the movable part of the variable resistor to move in a direction in which the amount of current is decreased.

An LED light bulb includes a bulb shell, a bulb base, two conductive supports, a stem, and an LED filament. The bulb base is connected with the bulb shell. The two conductive supports are disposed in the bulb shell. The stem extends from the bulb base to inside of the bulb shell. The LED filament includes a plurality of LED chips and two conductive electrodes. The LED chips are arranged in an array along an elongated direction of the LED filament. The two conductive electrodes are respectively disposed at two ends of the LED filament and connected to the LED chips. The two conductive electrodes are respectively connected to the two conductive supports. The LED filament is curled to satisfy symmetry characteristics.

A light emitting diode (LED) module is disclosed having an elongated flat support with a first long end, a second long end opposite the first long end, and electrically conductive regions. The disclosed LED module includes at least one LED mounted on the flat support as well as an electronic driver with at least one electronic driver component mounted on the flat support for driving the at least one LED. The electrically conductive regions have a first pair of contact points on one of the two long ends for connection of the LED module to a current source and a second pair of contact points on one of the two long ends for connection of a smoothing capacitor on the LED module.

A lighting apparatus includes a first electrode, a second electrode, a lighting source, a rectifier, a driver and an electric shock prevention circuit. The first electrode and the second electrode receive an external power source. The external power source is either an alternating current or a direct current. The light source has multiple LED modules. The rectifier is used for rectifying the external power source to a rectified power. The driver is used for converting the rectified power to a driving current supplying to the light source.

A lighting apparatus includes a first electrode, a second electrode, a lighting source, a rectifier, a driver and an electric shock prevention circuit. The first electrode and the second electrode receive an external power source. The external power source is either an alternating current or a direct current. The light source has multiple LED modules. The rectifier is used for rectifying the external power source to a rectified power. The driver is used for converting the rectified power to a driving current supplying to the light source.

An LED light bulb includes a bulb shell, a bulb base, two conductive supports, a stem, and an LED filament. The bulb base is connected with the bulb shell. The two conductive supports are disposed in the bulb shell. The stem extends from the bulb base to inside of the bulb shell. The LED filament includes a plurality of LED chips and two conductive electrodes. The LED chips are arranged in an array along an elongated direction of the LED filament. The two conductive electrodes are respectively disposed at two ends of the LED filament and connected to the LED chips. The two conductive electrodes are respectively connected to the two conductive supports. The LED filament is curled to satisfy symmetry characteristics.

An LED light bulb includes a bulb shell, a bulb base, two conductive supports, a stem, and an LED filament. The bulb base is connected with the bulb shell. The two conductive supports are disposed in the bulb shell. The stem extends from the bulb base to inside of the bulb shell. The LED filament includes a plurality of LED chips and two conductive electrodes. The LED chips are arranged in an array along an elongated direction of the LED filament. The two conductive electrodes are respectively disposed at two ends of the LED filament and connected to the LED chips. The two conductive electrodes are respectively connected to the two conductive supports. The LED filament is curled to satisfy symmetry characteristics. Surface roughness of segments of a portion of the LED filament in different quadrants in a top view or in a side view is in line symmetry or in point symmetry.

In one embodiment, a filament for LED filament lamp is presented, that includes a light-transmissive substrate; at least one LED die mounted on the light-transmissive substrate; and at least one current regulator mounted on the light-transmissive substrate, wherein the current regulator is connected in series with the at least one LED. In another embodiment, an LED filament lamp is presented, that includes a dimmable LED driver circuit; a first channel LED array with at least two LED die and a first forward voltage drop; and a second channel LED array with at least one LED dies and at least one current regulator to cause a second forward voltage drop of the second channel LED array to increase as current through the second channel LED array increases, wherein the second channel LED array is connected in parallel with the first channel LED array.

A self-monitoring LED marine navigation light that monitors LED intensity and if the intensity is not COLREG compliant, a microprocessor in the light simulates an open filament just as would an incandescent light, thus allowing the analog ships alarm panel circuit to trigger an alarm. The device generally comprises a base, a lens mounted to the base, and an LED module seated in the base and enclosed by the lens. The LED module includes primary and optional secondary LED lights plus one or more photodiode(s) exposed to the LED light(s). The LED also includes a processor and software for measuring light intensity input to the photodiode(s), comparing measured intensity to a minimum COLREG threshold, and signaling failure when measured intensity falls below said minimum threshold.

An LED light bulb includes a bulb shell, a bulb base, two conductive supports, a stem, and an LED filament. The bulb base is connected with the bulb shell. The two conductive supports are disposed in the bulb shell. The stem extends from the bulb base to inside of the bulb shell. The LED filament includes a plurality of LED chips and two conductive electrodes. The LED chips are arranged in an array along an elongated direction of the LED filament. The two conductive electrodes are respectively disposed at two ends of the LED filament and connected to the LED chips. The two conductive electrodes are respectively connected to the two conductive supports. The LED filament is curled to satisfy symmetry characteristics. Surface roughness of segments of a portion of the LED filament in different quadrants in a top view or in a side view is in line symmetry or in point symmetry.