ated objects are the one which reflect the light coming from the source. Luminous objects are which emit their own light and are considered as sources of light. 1. The incident ray, reflected ray and the normal to the plane, all lie on the same side of the plane.2. The angle of incidence is always equal to the abgle of reflection in case of a regular suface.Regular reflection is in which the angle of incidence is equal to the angle of reflection.A periscope is an instrument for observation over, around or through an object, obstacle or condition that prevents direct line-of-sight observation from an observer's current position. In its simplest form, it consists of an outer case with mirrors at each END set parallel to each other at a 45° angle.A kaleidoscope is a STRUCTURE CONSISTING of three plain mirrors JOINT with the reflective side FACING inwards and at and angle of 60 degrees.In a diffused reflection, the incident ray is reflected at many angles rather than one single angle.