A lightguide structure comprising: a first portion configured to receive light rays emitted by an external display ; a second portion configured to output the light rays from the first portion and ambient light incident on the second portion; and an intermediate portion configured to connect between the first portion and the second portion and reflect the light rays from the first portion for transferring the light rays to the second portion , wherein the second portion comprises: a plurality of first surfaces configured to reflect light rays from the first portion; and at least one second surface configured to output the ambient light and the light rays reflected from the plurality of first surfaces, the plurality of the first surfaces includes a plurality of surfaces which are inclined with respect to the second surface; the plurality of first surfaces includes at least one surface located between the inclined surfaces which is substantially parallel to the second surface; characterized in that the lightguide structure further comprises a compensating portion , and wherein a surface of the compensating portion is identical to the structure of the plurality of first surfaces of the second portion so that the compensating portion adjoins the second portion with no gap therebetween. a first portion configured to receive light rays emitted by an external display ; a second portion configured to output the light rays from the first portion and ambient light incident on the second portion; and an intermediate portion configured to connect between the first portion and the second portion and reflect the light rays from the first portion for transferring the light rays to the second portion , wherein the second portion comprises: a plurality of first surfaces configured to reflect light rays from the first portion; and at least one second surface configured to output the ambient light and the light rays reflected from the plurality of first surfaces, the plurality of the first surfaces includes a plurality of surfaces which are inclined with respect to the second surface; the plurality of first surfaces includes at least one surface located between the inclined surfaces which is substantially parallel to the second surface; characterized in that the lightguide structure further comprises a compensating portion , and wherein a surface of the compensating portion is identical to the structure of the plurality of first surfaces of the second portion so that the compensating portion adjoins the second portion with no gap therebetween. a plurality of first surfaces configured to reflect light rays from the first portion; and at least one second surface configured to output the ambient light and the light rays reflected from the plurality of first surfaces, the plurality of the first surfaces includes a plurality of surfaces which are inclined with respect to the second surface; the plurality of first surfaces includes at least one surface located between the inclined surfaces which is substantially parallel to the second surface; characterized in that the lightguide structure further comprises a compensating portion , and wherein a surface of the compensating portion is identical to the structure of the plurality of first surfaces of the second portion so that the compensating portion adjoins the second portion with no gap therebetween. <EOS>