Most light energy reflectors are based on conic sections such as parabolas, ellipses and circles.
Aconic reflector is a generic term used to explain a reflective curve outside these groups.
They are usually created with the intention of generating a specific result not achievable using conic curves.
They can be used to mask hot spots generated by the lamp envelope and cold areas created by shadows.
Examples include a search light reflector that is intentionally designed to generate a divergent beam, or a reflective curve with the intention of generating an aesthetic light effect.