led chip red light prism rod dichroic prism red blue relay lens and dichroic are arranged in a specific configuration in this configuration the optical axis of the red light led chip red light prism rod dichroic prism and red blue relay lens coincide with one another and at an angle of about 45 u00b0 to the face of the dichroic the blue light led chip blue light prism rod and dichroic prism are arranged in sequence with the optical axis of the blue light led chip blue light prism rod and dichroic prism coinciding with one another the dichroic prism is perpendicular to those of the red light prism rod and red blue relay lens the green light led chip green light prism rod green relay lens and dichroic are arranged in sequence with the optical axis of the green light led chip green light prism rod and green relay lens coinciding with one another and perpendicular to those of the red light prism rod dichroic prism and red blue relay lens the point of intersection between the optical axis of green light led chip green light prism rod green relay lens and that of the red light prism rod dichroic prism and the red blue relay lens is centered on the surface of the beam splitting film of the dichroic the beam splitting film on the adhesively joined section of the dichroic prism is a beam splitting film that transmits blue light but reflects red light the installation position of the red light led chip can be interchanged with that of the blue light led chip the face of the dichroic can be located anywhere around its own center in a.