A display device comprising: a display panel ; a guide panel coupled to a surface of the display panel via an attaching member , the guide panel including: a body portion facing the surface of the display panel in a first direction, a first light shielding portion protruding from the body portion in the first direction towards the surface of the display panel , the first light shielding portion closer to a center of the display panel than the attaching member , a first fastening portion protruding from the body portion in a second direction away from the first direction, and a second fastening portion protruding from the body portion in the second direction; and a cover including: a planar surface facing the display panel in the first direction, and a side surface part protruding from the planar surface towards the first direction, the side surface part inserted between the first fastening portion and the second fastening portion , characterised in that the attaching member is configured to pass through, between the display panel and the guide panel , to an exterior of the display device a portion of light corresponding to a predetermined wavelength, and to filter another portion of the light corresponding to another wavelength. a display panel ; a guide panel coupled to a surface of the display panel via an attaching member , the guide panel including: a body portion facing the surface of the display panel in a first direction, a first light shielding portion protruding from the body portion in the first direction towards the surface of the display panel , the first light shielding portion closer to a center of the display panel than the attaching member , a first fastening portion protruding from the body portion in a second direction away from the first direction, and a second fastening portion protruding from the body portion in the second direction; and a body portion facing the surface of the display panel in a first direction, a first light shielding portion protruding from the body portion in the first direction towards the surface of the display panel , the first light shielding portion closer to a center of the display panel than the attaching member , a first fastening portion protruding from the body portion in a second direction away from the first direction, and a second fastening portion protruding from the body portion in the second direction; and a cover including: a planar surface facing the display panel in the first direction, and a side surface part protruding from the planar surface towards the first direction, the side surface part inserted between the first fastening portion and the second fastening portion , a planar surface facing the display panel in the first direction, and a side surface part protruding from the planar surface towards the first direction, the side surface part inserted between the first fastening portion and the second fastening portion , characterised in that the attaching member is configured to pass through, between the display panel and the guide panel , to an exterior of the display device a portion of light corresponding to a predetermined wavelength, and to filter another portion of the light corresponding to another wavelength. <EOS>