Abstract: In one embodiment, an LED lamp has a generally bulb shape. The LEDs are low power types and are encapsulated in thin, narrow, flexible strips. The LEDs are connected in series in the strips to drop a desired voltage. The strips are affixed to the outer surface of a bulb form to provide structure to the lamp. The strips are connected in parallel to a power supply, which may be housed in the lamp. Since many low power LEDs are used and are spread out over a large surface area, there is no need for a large metal heat sink. Further, the light emission is similar to that of an incandescent bulb. In other embodiment, there is no bulb form and the strips are bendable to have a variety of shapes. In another embodiment, a light sheet is bent to provide 360 degrees of light emission. Many other embodiments are described.

Abstract: A solid state lamp, such as one that can replace an incandescent light bulb, has a base portion having an electrical connector for connection to a source of power, such as an Edison-type connector for connection to the mains voltage. An AC/DC converter in the base converts the mains voltage to a suitable light emitting diode (LED) drive voltage. A plurality of receptacles on the base connects to electrodes of plug-in modules. Each plug-in module supports a plurality of low power LEDs connected in series. The strings of LEDs on different modules are connected in parallel when connected to the receptacles. The modules and base are configured to allow a user to operate the lamp with different combinations of modules to generate a desired light output from the lamp. For example, the user can recreate the lumens equivalent of a 20 W, 40 W, or 60 W bulb by using one, two, or three modules.

Abstract: A solid state, bidirectional light sheet and method of fabricating the sheet are disclosed. In one embodiment, bare LED chips have top and bottom electrodes, where the bottom electrode is a large reflective electrode. An array of LEDs (e.g., 500 LEDs) is sandwiched between at least two transparent substrates having conductors bonded to the electrodes without wires. Various ways to connect the LEDs in series are described along with various embodiments. The light sheets are formed to emit light from opposite surfaces of the light sheet to create a bidirectional light sheet. The light sheet may be suspended from a ceiling to be perpendicular to the ceiling, or the angles of the light sheet may be adjusted. The suspended light sheet may form a cylinder for uniform illumination of the floor and ceiling. Lenses may be formed in the light sheet to emit light at any peak intensity angle to achieve any light emission pattern.

Abstract: A solid state light sheet and method of fabricating the sheet are disclosed. In one embodiment, bare LED chips have top and bottom electrodes, where the bottom electrode is a large reflective electrode. The bottom electrodes of an array of LEDs (e.g., 500 LEDs) are bonded to an array of electrodes formed on a flexible bottom substrate. Conductive traces are formed on the bottom substrate connected to the electrodes. A transparent top substrate having conductors is then laminated over the bottom substrate. Various ways to connect the LEDs in series are described along with many embodiments. The light sheets may be formed to emit light from opposite surfaces of the light sheet, enabling it to be used in a hanging fixture to illuminate the ceiling as well as the floor. The light sheet provides a practical substitute for a standard 2×4 foot fluorescent ceiling fixture.