Transmissive display device

A transmissive display device, comprising:

• a light source configured to emit light;
• a display part which receives the light from the light source to generate display light that represents an image;
• a deflecting element which changes a direction of the display light emitted from the display part;
• and
• a transmissive reflector configured to reflect light, which has a wavelength included in the display light emitted from the display part, towards a user and transmits light, which has other wavelengths, wherein
• the transmissive reflector includes:
• a diffracting element configured to deflect a direction of the display light;
• a front transparent member configured to hold the diffracting element at an incident side of the display light which is incident on the transmissive reflector;
• and
• a rear transparent member opposite to the front transparent member, the rear transparent member sandwiching the diffracting element together with the front transparent member,
• the front transparent member includes an air contact surface which contacts air,
• the diffracting element is inclined with respect to the air contact surface so that a difference between an incident angle of the incident display light on the diffracting element and an emission angle of the display light emitted from the diffracting element becomes small, and
• the diffracting element includes at least one inclined area, which is inclined with respect to the air contact surface, and one of a non-inclined area, which is not inclined with respect to the air contact surface, and a free-form surface, which has at least one curvature.