The art of Lichtenstein

I am very interested in the art of Lichtenstein because he uses dots to create different colours, like a white background and red dots on top to create a skin colour. This is called the Ben-day dot technique, Depending on the effect, colour and optical illusion needed, small coloured dots are closely spaced, widely spaced or overlapping. Magenta dots, for example are widely spaced to create pink. 1950's and 1960's pulp comic books used ben-day dots in the four process colours (cyan, magenta, yellow and black) to inexpensively create shading and secondary colours such as green, purple, orange and flesh tones.  Ben-day dots were considered the trademark of Lichtenstein's work, he enlarged and exagerated them in many of his work and sculptures and especially his interpretations of contemporary comic books like MARVEL. To apply the dots to a drawing Lichtenstein would purchase transparent overlay sheets. The overlay material was cut in the shapes of the tonal areas desired i.e. shadow or background or surface treatment and rubbed onto the specific areas of the drawing or canvas.