Imaging system having dual image sensors

1. An imaging system for capturing an image of an object comprising:

a first lens;

a dichroic beam splitter having a dichoric filter disposed between two prisms, wherein the dichroic filter transmits light of a color band and reflects light of all colors outside the color band;

a first image sensor for capturing an image formed by the transmitted light in the color band;

a second image sensor for capturing an image formed by the reflected light outside the color band;

wherein the first image sensor is a monochrome image sensor and the second image sensor is a color image sensor having a color filter array disposed on pixels of the second image sensor;

wherein the image captured by the first image sensor and the image captured by the second image sensor are combined to form a single color image;

wherein the dichroic beam splitter is a wafer level dichroic beam splitter singulated from a dichroic beam splitter wafer, and wherein the dichroic beam splitter wafer is produced by dicing diagonally a block comprising a plurality of planar substrate layers and a plurality of planar dichroic filter layers, each dichroic filter layer is disposed between two substrate layers.

2. The imaging system of claim 1 , wherein the first image sensor is a monochrome image sensor having no color filter array disposed on pixels of the first image sensor.

3. The imaging system of claim 1 , wherein the color band is green color band and the first image sensor is a green monochrome image sensor.

4. The imaging system of claim 1 , wherein the color filter array comprises red color filter.

5. The imaging system of claim 4 , wherein the color filter array further comprises one of blue and yellow color filters.

6. The imaging system of claim 4 , wherein the color filter array further comprises one of blue-red, red-blue, and red-yellow color filters.

7. The imaging system of claim 1 , wherein the first image sensor and the second image sensor are mounted on two sides of the dichroic beam splitter.

8. The imaging system of claim 1 further comprising a second lens disposed on the dichroic beam splitter opposite the first image sensor.

9. The imaging system of claim 1 , wherein the imaging system is installed in a mobile phone.

10. An electronic device comprising an imaging system for capturing an image of an object, the imaging system comprising:

a first lens;

a reflector for folding an optical path 90°;

a dichroic beam splitter having a dichoric filter disposed between two prisms, wherein the dichroic filter transmits light of a color band and reflects light of all colors outside the color band;

a first image sensor for capturing an image formed by the transmitted light in the color band;

a second image sensor for capturing an image formed by the reflected light outside the color band;

wherein the first image sensor is a monochrome image sensor and the second image sensor is a color image sensor having a color filter array disposed on pixels of the second image sensor;

wherein the image captured by the first image sensor and the image captured by the second image sensor are combined to form a single color image;

wherein the dichroic beam splitter is a wafer level dichroic beam splitter singulated from a dichroic beam splitter wafer, and wherein the dichroic beam splitter wafer is produced by dicing diagonally a block comprising a plurality of planar substrate layers and a plurality of planar dichroic filter layers, each dichroic filter layer is disposed between two substrate layers.

11. The electronic device of claim 10 , wherein the first image sensor and the second image sensor are mounted on two sides of the dichroic beam splitter.

12. The electronic device of claim 10 further comprising a second lens disposed on the dichroic beam splitter opposite of the first image sensor.

13. The electronic device of claim 10 , wherein the electronic device comprises a mobile phone.