Patent Application
20090108857
1. Field of Invention
The present invention relates to concentration-type solar cells and, more particularly, to an efficient, effective and inexpensive apparatus for testing concentration-type solar cells.
2. Related Prior Art
Solar cells are popular for being environmentally friendly and economic in use. The efficiencies of solar cells are becoming higher and higher while the prices are becoming lower and lower. Therefore, solar cells are getting more and more attention. To increase the efficiency of a solar cell and reduce the cost of the same, more and more effort are made to develop concentration-type solar cells of III-V compounds. Therefore, there is a need for an efficient and effective apparatus to test these tiny concentration-type solar cells of III-V compounds. Such an apparatus is however expensive.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art.
It is the primary objective of the present invention to provide an efficient, effective and inexpensive apparatus for testing concentration-type solar cells.
To achieve the foregoing objective, an apparatus includes a light source for emitting light, a focusing unit for focusing the light emitted from the light source and turning the same into a light beam, a testing unit for testing any one of solar cells of a wafer; and a wafer-positioning unit for moving the wafer horizontally and vertically, thus brining a targeted one of the solar cells into contact with the testing unit.
Other objectives, advantages and features of the present invention will become apparent from the following description referring to the attached drawings.
The present invention will be described via the detailed illustration of the preferred embodiment referring to the drawings.
Referring to
The light source 1 may be a light-emitting diode (“LED”), a solar simulator, a halogen lamp or any other proper lamp for use in any ordinary instrument. The light source 1 is used to emit light.
The focusing unit 2 may be an aperture defined in a plate or a condenser lens. The focusing unit 2 is used to focus the light emitted from the light source 1 and turns the light into a light beam 11.
As clearly shown in
The second workbench 32 includes a slot 321 defined therein, a screw 323 disposed in the slot 321 and a driving element 322 operatively connected to the screw 323. The second workbench 32 is provided on the first workbench 31. Although not shown, the second workbench 32 includes a nut attached to the bottom. The nut of the second workbench 32 is engaged with the screw 313 of the first workbench 31 so that the second workbench 32 is moved in a first direction when the screw 313 is rotated by the driving element 312 of the first workbench 31.
The elevator 33 is used to support a wafer 331. As clearly shown in
As clearly shown in
To test any one of the solar cells 3311 of the wafer 331 (the “target”), the light source 1 emits light. The focusing unit 2 focuses the light emitted from the light source 1 and turns the same into a light beam 11. At this instant, the wafer 331 is not in contact with the probes 341. Under the control of the computer 343, the driving elements 312 and 322 move the wafer 331 horizontally so that the target is right below the probes 341. Under the control of the computer 343, the driving element 332 lifts the wafer 331 and brings the target into contact with the probes 341. The probes 341 acquire various parameters of the target such as the open circuit voltage, the short circuit current, the maximum voltage and the maximum current. Based on these parameters, the computer 343 calculates the fill factor and the photo-electric conversion efficiency of the target.
As discussed above, the present invention provides an efficient, effective and inexpensive the apparatus for testing concentration-type solar cells.
The present invention has been described via the detailed illustration of the preferred embodiment. Those skilled in the art can derive variations from the preferred embodiment without departing from the scope of the present invention. Therefore, the preferred embodiment shall not limit the scope of the present invention defined in the claims.
