Projection optical path and projection device

A projection optical path system, comprising:

• a triple light source system emitting a first converged light;
• a single light source system emitting a light with a monochromatic wavelength, wherein the first converged light and the light with the monochromatic wavelength are crossed and converged;
• wherein the triple light source system comprises a first light source, a second light source and a fourth light source, the first light source emits a light with a first wavelength, the second light source emits a light with a second wavelength, the fourth light source emits a light with a fourth wavelength, the light with the second wavelength and the light with the fourth wavelength are converged to form a second converged light, the second converged light and the light with the first wavelength are converged to form the first converged light, the single light source system comprises a third light source, the third light source emits a light with a third wavelength, the light with the first wavelength, the light with the second wavelength and the light with the third wavelength have different colors, the light with the first wavelength, the light with the second wavelength, and the light with the third wavelength are respectively one of red light, green light and blue light, and a wavelength range of the light with the fourth wavelength is within a wavelength range of the red light, and
• wherein a wavelength of the light with the fourth wavelength is defined as λ1, the wavelength of the red light among the light with the first wavelength, the light with the second wavelength and the light with the third wavelength is λ2, and λ1≠λ2;
• and
• an excitation light source emitting an excitation light, wherein the excitation light is emitted to the triple light source system or the single light source system,
• wherein the triple light source system further comprises a first beam splitter, the first beam splitter is disposed at a crossing position of the second converged light and the light with the first wavelength, and the excitation light source is disposed at a side of the first beam splitter away from the second light source,
• wherein:
• the first light source is a green light source, a surface of the first beam splitter facing the excitation light source is provided with a reflective film for the excitation light, and the excitation light is reflected by the first beam splitter towards the first light source, or
• the second light source is a green light source, a surface of the first beam splitter facing the excitation light source is provided with an anti-reflection film for the excitation light, and the excitation light is transmitted towards the second light source,
• wherein the triple light source system further comprises a second beam splitter, the second beam splitter is disposed at a crossing position of the light with the second wavelength and the light with the fourth wavelength, a surface of the second beam splitter facing the second light source is provided with an anti-reflection film for the light with the second wavelength, and a surface of the second beam splitter facing the fourth light source is provided with a reflective film for the light with the fourth wavelength,
• wherein the projection optical path system further comprises a third beam splitter, the third beam splitter is disposed at a crossing position of the first converged light and the light with the third wavelength, wherein the light with the first wavelength, the light with the second wavelength, the light with the third wavelength and the light with the fourth wavelength are converged by the third beam splitter so as to be emitted, and
• wherein the light with the first wavelength is a green light, the light with the second wavelength is a red light, the light with the third wavelength is a blue light, a surface of the third beam splitter facing the first light source is provided with an anti-reflection film for the green light and the red light, and a surface of the third beam splitter facing the third light source is provided with a reflective film for the blue light.