Question

which among the following mono chromatic lies has more frequency option A red option B green option C yellow option option d blue

Answer 1

In the case of laser-based RGB sources, the red, green and blue beams usually have a relatively narrow optical bandwidth, i.e. they are close to monochromatic. In the chromaticity diagram, such beams are associated with points at the border of the colored region. By mixing, e.g., three monochromatic beams, all those colors can be reproduced which lie in the triangle spanned by the corresponding points. For comparison, the accessible color range for a cathode tube display, a lamp-based beamer or a color printer is a triangle with the edges lying well inside the diagram, so that the spanned area is usually much smaller. A significant further improvement of a laser-based projection system would be to add a fourth wavelength.