Abstract: An image sensor having increased number of pixels. The image sensor includes a substrate, a frame layer, a photosensitive chip, wires, an adhesive medium and a transparent layer. The substrate has an upper surface and a lower surface. The frame layer is arranged on the upper surface of the substrate to form a cavity together with the substrate. The photosensitive chip is arranged within the cavity and is mounted to the upper surface of the substrate. The wires electrically connect the photosensitive chip to the substrate. The adhesive medium is inside the cavity. The transparent layer is arranged on the frame layer to cover the image sensor. Thus, the particles inside the cavity fall down and are adhered to the adhesive medium without being distributed over the sensitive area of the photosensitive chip and the transparent layer. Therefore, the number of good pixels of the sensor may be increased.