Light reflection device and mobile object

A mobile object comprising:

• a light reflection device including
• a light source to emit irradiation light,
• a reflector to reflect the irradiation light emitted from the light source, the reflector having a first plane,
• a housing;
• and
• a holder attached to the housing to hold the reflector,
• a screen on which an image is formed by the irradiation light reflected by the reflector;
• a front windshield to reflect the irradiation light diverged and projected through the screen;
• and
• an imaging optical system to project the irradiation light emitted from the screen toward the front windshield,
• wherein the holder has a second plane contacting the first plane, the holder restricts a movement of the reflector and allows a size of the reflector to change in contrast with the holder,
• the reflector and the holder are disposed such that the first plane is located further from the housing than the second plane in a direction perpendicular to the first plane and the second plane, and
• a difference between a linear expansivity of the holder and a linear expansivity of the housing is smaller than a difference between a linear expansivity of the reflector and the linear expansivity of the housing.

A light reflection device comprising:

• a light source to emit irradiation light;
• a reflector to reflect the irradiation light emitted from the light source;
• a housing;
• and
• a holder attached to the housing to hold the reflector, the reflector having a first plane,
• wherein the holder has a second plane contacting the first plane, the holder restricts a movement of the reflector and allows a size of the reflector to change in contrast with the holder,
• the reflector and the holder are disposed such that the first plane is located further from the housing than the second plane in a direction perpendicular to the first plane and the second plane, and
• a difference between a linear expansivity of the holder and a linear expansivity of the housing is smaller than a difference between a linear expansivity of the reflector and the linear expansivity of the housing.