Why are reflector telescopes inherently free of chromatic aberration?

Answer

Because the primary optical element reflects light rather than passing it through glass.

Reflectors utilize a mirror for focusing, and since the light bounces off the front surface, it never passes through any medium that would cause the spectral separation inherent to refraction in glass.

Why are reflector telescopes inherently free of chromatic aberration?

#Videos

What Are Two Disadvantages Of Refracting Telescopes? - YouTube

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