An optical system, comprising: a reflective polarizer; and a display and a mirror disposed on a same side of, and generally facing, the reflective polarizer, for normally incident light in a predetermined wavelength range extending across at least a portion of a visible spectrum: the reflective polarizer transmitting at least 80% of the incident light having a first polarization state and reflecting at least 80% of the incident light having an orthogonal second polarization state; and the mirror reflecting at least 80% of the incident light for each of the first and second polarization states; the display adapted to emit an image for viewing by a viewer, the emitted image comprising an emitted central image cone emitted from a central location of the display, the emitted central image cone comprising an emitted central image ray emitted from the central location of the display at a central emission angle (Θ e) greater than about 5 degrees, the reflective polarizer receiving the emitted central image ray at a first incident angle (Θ i1) at a central location of the reflective polarizer and reflecting at least 80% of the received mitted central image ray as a first reflected image ray, the mirror receiving the first reflected image ray at a second incident angle (Θ i2) at a central location of the mirror and reflecting at least 80% of the received first reflected image ray as a second reflected image ray (15b"), the reflective polarizer receiving and transmitting at least 80% of the second reflected image ray (15b"), the central locations (10c, 20c, 30c) of the display, the reflective polarizer and the mirror defining a midplane comprising first, second and third regions (R1, R2, R3), such that for emitted image rays emitted from the display and propagating along and in the midplane and prior to being incident on the reflective polarizer for a second time: the first region comprises the emitted image rays that pass at least once across the first region; the second region comprises the emitted image rays that pass at least twice across the second region; and the third region comprises the emitted image rays that pass three times across the third region; the first, second and third regions (R1, R2, R3) having respective areas A1, A2 and A3, A3/A2 ≥ 0.3, wherein the first incident angle (Θ i1) is between about 25 and 35 degrees. a reflective polarizer; and a display and a mirror disposed on a same side of, and generally facing, the reflective polarizer, for normally incident light in a predetermined wavelength range extending across at least a portion of a visible spectrum: the reflective polarizer transmitting at least 80% of the incident light having a first polarization state and reflecting at least 80% of the incident light having an orthogonal second polarization state; and the mirror reflecting at least 80% of the incident light for each of the first and second polarization states; the display adapted to emit an image for viewing by a viewer, the emitted image comprising an emitted central image cone emitted from a central location of the display, the emitted central image cone comprising an emitted central image ray emitted from the central location of the display at a central emission angle (Θ e) greater than about 5 degrees, the reflective polarizer receiving the emitted central image ray at a first incident angle (Θ i1) at a central location of the reflective polarizer and reflecting at least 80% of the received mitted central image ray as a first reflected image ray, the mirror receiving the first reflected image ray at a second incident angle (Θ i2) at a central location of the mirror and reflecting at least 80% of the received first reflected image ray as a second reflected image ray (15b"), the reflective polarizer receiving and transmitting at least 80% of the second reflected image ray (15b"), the central locations (10c, 20c, 30c) of the display, the reflective polarizer and the mirror defining a midplane comprising first, second and third regions (R1, R2, R3), such that for emitted image rays emitted from the display and propagating along and in the midplane and prior to being incident on the reflective polarizer for a second time: the first region comprises the emitted image rays that pass at least once across the first region; the second region comprises the emitted image rays that pass at least twice across the second region; and the third region comprises the emitted image rays that pass three times across the third region; the first, second and third regions (R1, R2, R3) having respective areas A1, A2 and A3, A3/A2 ≥ 0.3, wherein the first incident angle (Θ i1) is between about 25 and 35 degrees. the reflective polarizer transmitting at least 80% of the incident light having a first polarization state and reflecting at least 80% of the incident light having an orthogonal second polarization state; and the mirror reflecting at least 80% of the incident light for each of the first and second polarization states; the first region comprises the emitted image rays that pass at least once across the first region; the second region comprises the emitted image rays that pass at least twice across the second region; and the third region comprises the emitted image rays that pass three times across the third region;