Patent ID: 9243761
Filing Date: 2016-01-26
CPC Classification: F21K,G02B,G03B,H01S

Claim Text:
1. A method to assemble an optical assembly having a red laser diode (LD), a green LD, a blue LD, a first lens, a second lens, a third lens, and a base to mount the red, green and blue LDs, and the first to third lenses, the optical assembly outputting multiplexed light containing red light emitted from the red LD, green light emitted from the green LD, and blue light emitted from the blue LD, the method comprising steps of: mounting a first LD among the red, green and blue LDs on a top surface of the base such that the first LD emits first light projecting on a first point on a virtual plane after transmitted through the first lens, the virtual plane being placed apart by at least one meter from the base, the first point being positioned on a line corresponding to the top surface of the base; mounting a second LD among the red, green and blue LDs except for the first LD on the top surface of the base such that the second LD emits second light projecting on a second point on the virtual plane after transmitted through the second lens, the second point being positioned on the line; mounting a third LD among the red, green and blue LDs except for the first and second LDs on the top surface of the base such that the third LD emits third light projecting on a third point on the virtual plane after transmitted through the third lens, the third point being positioned on the line; after mounting the second LD, mounting a first wavelength selective filter (WSF) on the top surface of the base, wherein the first WSF transmits one of the first light transmitted through the first lens and the second light transmitted through the second lens but reflects another of the first light transmitted through the first lens and the second light transmitted through the second lens, such that one of the first light and the second light reflected by the first WSF projects on a point on the virtual plane on which another of the first light transmitted through the first lens and the second light transmitted through the second lens projects, the first WSF outputting a mid-multiplexed light containing the first light and the second light; and mounting a second WSF on the top surface of the base, wherein the second WSF transmits one of the mid-multiplexed light and the third light transmitted through the third lens but reflects another of the mid-multiplexed light and the third light transmitted through the third lens, such that one of the mid-multiplexed light and the third light reflected by the second WSF projects on a point on which another of the mid-multiplexed light and the third light transmitted through the second WSF projects, the second WSF outputting the multiplexed light.