Lighting device having energy conversion module

The present invention provides a lighting device having an energy conversion module, comprising a lamp and at least one energy conversion module. The lamp includes a shade and a lamp tube. The lamp tube is disposed beneath the shade, and the inner wall surface of the shade can reflect light from the lamp tube. The energy conversion module is configured inside the shade or disposed on a lamp grid to receive light energy and convert it into electrical energy. As such, the lighting device can give light to photovoltaic cells in the environment so that electrical energy is generated. The object of converting part of the light energy into electrical energy for further utilization can thus be achieved.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a lighting device having an energy conversion module, and more particularly, to a lighting device equipped with an energy conversion module that receives light energy from a variety of commonly used lamps, such as fluorescent lamps, and converts the light energy into electrical energy.

2. Description of the Related Art

The use of lighting devices is universally prevalent. Along with the progression of time, the technology of lamps also evolves, from the use of incandescent light bulbs to fluorescent tubes and to white light-emitting diodes (LEDs) nowadays. The evolution is not only about new lamp styles, but also about improvements in illumination efficiency. Fluorescent lamps are one type of lighting devices commonly used; usually, there is a reflection layer coated on the metal support, e.g., the shade, of the fluorescent tube for enhancing the illumination effect (illuminance) and improving energy efficiency. Conventional lighting devices are used typically for illumination only. How to make further use of light sources to enhance energy utilization efficiency is a meaningful task.

A photovoltaic cell absorbs light energy to generate electricity. For instance, silicon-based solar cells absorb sunlight to produce electricity. But such solar cells are not efficient in absorbing light energy generated by indoor lighting devices. By contrast, dye-sensitized solar cells can absorb both indoor and outdoor light, including sunlight and light from lighting devices, and exhibit better energy conversion efficiency. A dye-sensitized solar cell (DSSC) converts light energy into electrical energy by a photoelectrochemical energy conversion mechanism. Its operation principle is different from that of a silicon crystal solar cell or a thin film solar cell which uses silicon as material. A DSSC generally consists of two pieces of transparent conducting oxide (TCO) glasses: one TCO glass is an electrode on which semiconductor oxide material such as nanocrystalline titanium oxide (TiO2) layer is deposited; the other is a counterelectrode which has platinum thin film on it. In between two electrodes, there are electrolyte and dye molecules adsorbed in TiO2layer. After the two electrodes are properly packaged and sealed, a DSSC is completed. When sun light irradiates a DSSC, the dye molecules release electrons that pass through the TiO2layer and TCO layer to an outer circuit for generating electricity. The electrons then go to the counterelectrode, where they undergo the electrocatalytic activity of the platinum and redox reaction of the electrolyte, and return to the dye molecules to complete the cycle. A DSSC absorbs solar energy within the range of visible light spectrum. In addition to absorbing solar radiation in an outdoor environment to generate electricity, a DSSC can also generate electricity at lower light intensity either in an indoor environment or under lighting devices; therefore it can be used in both outdoor and indoor environments. Besides, a DSSC uses more common materials, such as conducting glass, titanium oxide, platinum, electrolyte and dye. Also, manufacturing a DSSC does not require expensive equipments such as PECVD equipment, but requires only inexpensive equipments like screen printers, sintering ovens, etc. Therefore, compared with silicon-based solar cells, DSSCs are advantageous in reducing manufacturing cost. A DSSC can have various colors based on the dyes it uses, and it can also be made on flexible substrates. The DSSC is a new-generation solar cell of multiple applications. In sum, using such dye-sensitized solar cell to absorb light energy and convert it into electrical energy for use in other devices can enhance energy utilization efficiency and facilitate uses of products.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide an indoor lighting device having an energy conversion module that irradiates a photovoltaic cell, which can thus generate electrical energy for further application.

Another object of the present invention is to provide a lighting device having an energy conversion module that can supply electricity to electrical appliances or to rechargeable batteries. The energy conversion module comprises a photovoltaic cell and a power output unit so that through the module, light energy can be converted into electrical power output. The photovoltaic cell may include silicon-based solar cell, thin-film solar cell, or dye-sensitized solar cell. And the circuit module of the power output unit comprises a boost circuit to boost the power.

To achieve the aforesaid objects, the lighting device having an energy conversion module of the invention comprises a lamp and at least one energy conversion module, the lamp comprising a shade and a lamp tube, the lamp tube being disposed beneath the shade. The inner wall surface of the shade is able to reflect light from the lamp tube. The energy conversion module is disposed on the inner wall surface of the shade to receive light from the lamp tube and convert the light energy into electrical energy. The reflective surface of the shade has a first wall surface, a third wall surface, and a second wall surface connected to the first and the third wall surfaces respectively. The energy conversion module is disposed on the second wall surface, on the first wall surface, or on the third wall surface. Furthermore, the width of the energy conversion module is equal to or less than the diameter of the lamp tube.

In another embodiment of the invention, the lighting device having an energy conversion module comprises a lamp and at least one energy conversion module, the lamp comprising a shade, a lamp grid, and a lamp tube. The shade and the lamp grid are adjoined together such that the lamp tube is situated inside the shade and the lamp grid, and the inner wall surfaces of both the shade and the lamp grid can reflect light from the lamp tube. The lamp grid comprises a longitudinal rib and a horizontal rib. The energy conversion module is disposed on the longitudinal rib or on the horizontal rib of the lamp grid wall to receive light from the lamp tube and convert the light energy into electrical energy.

In yet another embodiment of the invention, the lighting device having an energy conversion module comprises a lamp having a base, a shade and a light source set, the light source set being situated inside the shade, and the light source set and the shade being disposed on the base; an LED assembly disposed at the periphery of the lighting device; and an energy conversion module disposed on the base to receive light from the light source set, convert the light energy into electrical energy, and supply it to the LED assembly. The light source set comprises a mount and a light source, the light source being electrically connected to the mount. The light source is a light bulb, lamp tube, LED light or fluorescent light.

In the present invention, the photovoltaic cell can be disposed at a proper location between the lamp tube and the shade, on the longitudinal rib or horizontal rib of the lamp grid wall, or on the lamp base to fully utilize the source of illumination and enhance energy utilization efficiency. Hence, this invention is a novel invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is to provide an indoor lighting device having an energy conversion module. The energy conversion module of the invention is an assembly of a photovoltaic cell and a power output unit. The photovoltaic cell is a solar cell, which may include silicon-based solar cell, thin-film solar cell, dye-sensitized solar cell and other types of solar cell with equivalent effect.FIG. 1illustrates a dye-sensitized solar cell used in an embodiment of the present invention. The dye-sensitized solar cell comprises a first electrode100, a second electrode200, and a nano-layer300sandwiched between them. The first electrode100comprises a first conductive glass layer101and a platinum catalyst layer102. The first conductive glass layer101comprises a first glass layer103and a first transparent conductive oxide thin film104such that the platinum catalyst layer102is adhered to the surface of the first transparent conductive oxide thin film104. The second electrode200comprises a second conductive glass layer201having a second glass layer202and a second transparent conductive oxide203. The nano-layer300includes a oxide-semiconductor thin film301, a plurality of dye molecules adsorbed thereto, and an electrolyte303. Thus, when the dye-sensitized solar cell receives light energy, it will emit electrons, which are transmitted to external lines via the oxide-semiconductor thin film and the conductive glass layer for supplying electricity.

As shown inFIG. 2, the power output unit400of the invention enables the energy conversion module20to supply electricity. The circuit module of the power output unit400includes a boost circuit401to boost the voltage before output. The power output of the invention can supply electricity to a rechargeable battery or an electrical appliance, such as an LED unit, a lamp unit, a decorative unit with light source, or any equivalent unit.

FIG. 3,FIG. 4andFIG. 5are respectively a perspective view, a sectional view, and a layout view of a plurality of energy conversion modules according to the first embodiment of the invention. As shown inFIG. 1andFIG. 2, the lighting device of the invention comprises a lamp10and at least one energy conversion module20mounted therein. The lamp10comprises a shade11and a lamp tube12, which is disposed beneath or inside the shade11. In order to reflect light for enhancing illuminance, a reflective surface13is provided on the inner wall surface of shade11to reflect light emitted from the lamp tube12. The energy conversion module20is disposed inside the shade11. In this embodiment, the energy conversion module20is disposed on the inner wall surface of the shade11to receive light emitted from the lamp tube12and convert the light energy into electrical energy. The inner wall surface of the shade11has a first wall surface111, a third wall surface113, and a second wall surface112connected respectively to the first wall surface111and the third wall surface113. The first wall surface111and the third wall surface113are not on the same plane as the second wall surface112. The first wall surface111and the second wall surface112are obtuse angled, and the third wall surface113and the second wall surface112are obtuse angled as well. The energy conversion module20is disposed on the second wall surface112, on the third wall surface113, or on the first wall surface111. The energy conversion module20can also be situated at both ends, or at either end, of the second wall surface112. In this embodiment, the width of the energy conversion module20is equal to or less than the diameter of the lamp tube12so as to avoid reducing the overall illuminance and to convert part of the light energy into electrical energy as well.

As shown inFIG. 5, one or a plurality of energy conversion modules20are arranged at any location on the inner wall surface, including the first wall surface111, the second wall surface112, and the third wall surface113, of the shade11. If a plurality of energy conversion modules20are to be arranged for the lamp, they must be electrically interconnected in order to supply power to a rechargeable battery or to an electrical appliance30.

FIG. 6is a perspective view of a lighting device having an energy conversion module according to the second embodiment of the invention. The embodiment shows a table lamp where the energy conversion module20is disposed on the inner wall surface of the shade14and situated above the lamp tube15, and the width of the energy conversion module20is equal to or less than the diameter of the lamp tube15. The energy conversion module20is electrically connected to the charger inside the lamp base, or to an LED unit31. If a charger is provided at the lamp base, the charger can be connected further to a handheld device, e.g. mobile phone, for charging it. Additionally, a rechargeable battery may be arranged inside the lamp base, storing electricity coming from the power output. The rechargeable battery can then supply power to a charger if applicable. Naturally, chargers of various specifications in accordance with different handheld devices can be provided for the lamp base.

FIG. 7andFIG. 8are respectively a sectional view and a top view of a lighting device having an energy conversion module according to the third embodiment of the invention. As shown, the lighting device comprises a lamp40and at least one energy conversion module20. The lamp40comprises a shade41, a lamp grid42, and a lamp tube43. The shade41and the lamp grid42are adjoined together such that the lamp tube43is situated between the shade41and the lamp grid42, wherein the lamp grid42and the wall surfaces of the shade41can reflect light from the lamp tube43. The lamp grid42has a longitudinal rib421and a horizontal rib422. The energy conversion module20is disposed at the longitudinal rib421or at the horizontal rib422to receive light from the lamp tube43and convert the light energy into electrical energy. Moreover, the longitudinal rib421or the horizontal rib422of the lamp grid42may be replaced by the energy conversion module20, that is, a dye-sensitized solar cell can be used as the longitudinal rib421or as the horizontal rib422. As such, when the energy conversion module20is irradiated by light, electricity is generated that can be supplied to various kinds of electrical appliances or chargers. The energy conversion module20includes a dye-sensitized solar cell.

FIG. 7shows a plurality of energy conversion modules20electrically interconnected that supply electricity to a rechargeable battery or to an electrical appliance30.

As shown inFIG. 8, the longitudinal ribs421and the horizontal ribs422of the lamp grid are vertically connected. In this embodiment of the invention, the energy conversion modules20are mounted on certain area of the longitudinal ribs421and422. As described above, the longitudinal ribs421and422can be directly replaced by the energy conversion modules20, which will absorb some part of the light, convert it into electricity, and supply the electricity to appliances.

A silicon-based solar cell or a dye-sensitized solar cell can be used in the present invention. Table 1 shows the power generated at different illuminance.

In one experiment example, three 3.5 cm×4.7 cm dye-sensitized solar cells were used, which could produce a current of 20-50 mA and a voltage of 0.6-2.1V. These solar cells were installed inside the shade of the fluorescent lamp and situated right above the lamp tube. The lamp fixture was a dual-tube one, FV-H2277-H made by China Electric MFG. In this embodiment, only one lamp tube, a tri-wavelength tube TLC 18W/865 of Philips, was used. The illuminance range of the lamp was 600-1230 lux. The illuminance meter was placed about 40-60 cm below the lamp tube. The experiment found that when three dye-sensitized solar cells were used, the percentage of illuminance to original illuminance (intensity measured without solar cells) was 98-99.2% as shown inFIG. 9.

FIG. 10andFIG. 11are respectively a sectional view and a top view of a lighting device having an energy conversion module according to the fourth embodiment of the invention. In this embodiment, the lighting device comprises a lamp51having a base511, a shade512and a light source set513, the light source set512being disposed inside the shade512, and the light source set513and the shade512being mounted on the base511; an LED assembly52disposed at the periphery of the lamp51; and an energy conversion module53disposed on the base511that receives light from the light source set513, converts the light energy into electrical energy, and supplies the electrical energy to the LED assembly. The energy conversion module53is a photovoltaic cell, such as a silicon-based solar cell, thin-film solar cell, or dye-sensitized solar cell. The energy conversion module53comprises a dye-sensitized solar cell and a power output unit enabling the energy conversion module to convert light energy into electricity. The circuit module of the power output unit includes a boost circuit to boost the voltage of power before output. Other components of the lighting device in this embodiment are identical to those described above and will not be elaborated here. The light source set513includes a mount514and a light source515, the light source515being electrically connected to the mount514. The light source is a light bulb, lamp tube, LED light or fluorescent tube.

As described above, the present invention uses a lighting device to irradiate photovoltaic cells indoor that enables the photovoltaic cells to produce electrical energy, wherein an energy conversion module disposed on the lighting device can convert part of the light energy into electrical energy. The invention provides improved functions and therefore meets the essential requirements of a patent.