Hand-held scanner

A hand-held scanner comprising:

• a body in a longitudinal direction;
• and
• an optical engine provided in the body and configured to output light,
• wherein the optical engine comprises:
• a lighting unit configured to emit, along a first axis, light generated from at least one light source;
• a prism unit comprising:
• a first prism via which an angle of light incident from the lighting unit through a first surface is changed and the light is transmitted to a second prism through a second surface;
• and
• the second prism via which light received from the first prism is transmitted to a light modulator, and light reflected from the light modulator is transmitted to a projection unit, and
• the projection unit configured to project light transmitted through the second prism, along a second axis being parallel to the first axis, and
• wherein directions of the first axis and the second axis are equal,
• wherein the lighting unit further comprises:
• a light equalizing unit configured to allow light generated from the at least one light source to have a uniform distribution on a surface to which the light is emitted;
• and
• a relay unit configured to relay light output from the light equalizing unit to the prism unit,
• wherein the relay unit comprises a first relay lens, a mirror and a second relay lens which are configured to focus light output from the light equalizing unit to the light modulator,
• wherein the mirror is slanted within a preset range of an acute angle with respect to the first axis, and
• wherein the first relay lens is a lens having a negative refractive power and the second relay lens is a lens with an aspherical surface having a positive refractive power.