👉 Apochromatic, also known as achromatic, is a term used in optical microscopy to describe an object that appears blue when viewed through a blue filter. This phenomenon occurs because of the way light behaves at different wavelengths, which results in a color difference between objects at different angles and distances. In the case of apochromatic objects, the object appears blue due to the interference of light from two different colors, typically blue and red. When an object is placed in front of a blue filter
