Quick Answer: The Primary Colours Filters are a set of 3 filters in red, green and blue, each transmitting one primary colour of light while reducing or absorbing the rest. They are used for light transmission and additive colour mixing lessons.
Last updated: October 2026
Key Features
Set of 3 filters: red, green and blue
Each filter transmits its own colour and reduces or absorbs other parts of visible light
Coloured beams from separate filters can be overlapped for additive colour mixing
Used with a light source, ray box, filter holder, optical bench or screen
Can be paired with secondary colour filters and colour triangle charts
Shining light through each filter onto a white screen shows students that a filter selects a colour rather than adding one. When red, green and blue beams are overlapped, students see new colours form by additive mixing and can compare the results with the RGB model.
Frequently Asked Questions
What colours are in the Primary Colours Filters set?
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