1. Field of the Invention
The present invention relates to a sensing device, and particularly to an image sensing device.
2. Description of the Related Art
FIG. 1 is a schematic, cross-sectional view of a conventional image sensing device. FIG. 2 is a schematic view of a wafer including a number of image sensing devices shown in FIG. 1. Referring to FIG. 1 and FIG. 2, the image sensing device 100 sawed from the wafer 50 includes an image sensing chip 110, a spacer 120, a protecting glass 130 and a lens module 140. An image sensing region 112 is defined on a front surface 111 of the image sensing chip 110. The image sensing region 112 includes a number of light sensitive units 114 arranged in an array. Color filter patterns 116 are respectively disposed on the light sensitive units 114, and micro lenses 118 are respectively disposed on the color filter patterns 116. Additionally, the spacer 120 is disposed on the front surface 111 of the image sensing chip 110 and around the image sensing region 112. The spacer 120 is configured for supporting the protecting glass 130. The lens module 140 is disposed on the protecting glass 130.
In the conventional technique, the protecting glasses 130 over the wafer 50 are a whole and the lens modules 140 over the wafer 50 are also a whole. In other words, the protecting glasses 130 are separated each other by a sawing process of the wafer 50, and the lens modules 140 are separated each other by the sawing process of the wafer 50. Thus, an orthogonal projection area of the lens module 140 on the front surface 111 of the image sensing chip 110 is equal to the area of the front surface 111 of the image sensing chip 110.
The protecting glass 130 in the conventional image sensing device 100 can support the lens module 140 and prevent the image sensing region 112 from particles. However, the spacer 120 is needed to support the protecting glass 130 in the conventional image sensing device 100. The image sensing device 100 will be thickened due to thickness of the spacer 120 and the thickness of the protecting glass 130. Furthermore, a poor flatness of the spacer 120 and a poor flatness of the protecting glass 130 will affect the transmission path of the light, thereby reducing the quality of the image sensing device 100. In addition, it is very difficult for the protecting glass 130 to have a transparence of 100%, thereby reducing a light utility efficiency of the image sensing device 100.
Therefore, what is needed is an image sensing device to overcome the above disadvantages.