Abstract: An optical functional film for a head-up display according to the present disclosure includes (A) two or more phase difference layers and (B) an adhesive layer. The adhesive layer is adjacent to at least one phase difference layer, and an absolute value of difference between a refractive index of the adhesive layer and a refractive index of the phase difference layer adjacent to the adhesive layer in a direction of a fast axis is less than 0.060.

Abstract: A head-up display system including an optical laminate having at least one substrate material and a half-wave plate, and a display unit that makes display light representing a display image into S-polarized light or P-polarized light and emits the S-polarized light or the P-polarized light. In the head-up display system, an angle formed by a polarization axis of the S-polarized light or the P-polarized light incident from a position inclined at not less than 45° and not more than 65° with respect to an axis perpendicular to a surface of the optical laminate and a slow axis of the half-wave plate is not less than 35° and not more than 44°.

Abstract: The present disclosure relates to an optical film including an optical laminate in which two or more light reflection layers having center wavelengths of reflection different from each other are laminated and a polarizing element layer. The two or more light reflection layers are selected from at least one light reflection layer RPRL having a center wavelength of selective reflection in the range of 400 nm or more and 900 nm or less, in which a cholesteric liquid crystal phase with a right-handed spiral structure having right-handed circularly polarized light reflectivity is fixed, and at least one light reflection layer LPRL having a center wavelength of selective reflection in the range of 400 nm or more and 900 nm or less, in which a cholesteric liquid crystal phase with a left-handed spiral structure having left-handed circularly polarized light reflectivity is fixed.

Abstract: A light reflection film includes at least one light reflection layer RPRL in which a cholesteric liquid crystal phase of a right-handed helical structure having right circularly polarized light reflection ability is fixed; and at least one light reflection layer LPRL in which a cholesteric liquid crystal phase of a left-handed helical structure having left circularly polarized light reflection ability is fixed. A total of three or more layers of the light reflection layer(s) RPRL and the light reflection layer(s) LPRL are laminated. The light reflection layer(s) RPRL and the light reflection layer(s) LPRL laminated each have a selective reflection center wavelength shifted by an interval of 10 nm or more and 160 nm or less between two light reflection layers adjacent to each other.

Abstract: An optical laminate structure includes a light control laminate having at least one light reflection layer, a first quarter wave plate laminated on one of surfaces of the light reflection layer, and a second quarter wave plate laminated on another surface of the light reflection layer. The light reflection layer includes a right-handed circularly polarized light reflection layer or a left-handed circularly polarized light reflection layer, and an angle formed by a polarization axis of the S-polarized light or P-polarized light incident from a position inclined from an axis perpendicular to a surface of the light control laminate by 45° or more and 65° or less and a slow axis of the first quarter wave plate on a side to which the S-polarized light or P-polarized light is incident is 5° or more and less than 45°.

Abstract: A head-up display system including an optical laminate having at least one substrate material and a half-wave plate, and a display unit that makes display light representing a display image into S-polarized light or P-polarized light and emits the S-polarized light or the P-polarized light. In the head-up display system, an angle formed by a polarization axis of the S-polarized light or the P-polarized light incident from a position inclined at not less than 45° and not more than 65° with respect to an axis perpendicular to a surface of the optical laminate and a slow axis of the half-wave plate is not less than 35° and not more than 44°.

Abstract: A light reflection film includes at least one light reflection layer RPRL in which a cholesteric liquid crystal phase of a right-handed helical structure having right circularly polarized light reflection ability is fixed; and at least one light reflection layer LPRL in which a cholesteric liquid crystal phase of a left-handed helical structure having left circularly polarized light reflection ability is fixed. A total of three or more layers of the light reflection layer(s) RPRL and the light reflection layer(s) LPRL are laminated. The light reflection layer(s) RPRL and the light reflection layer(s) LPRL laminated each have a selective reflection center wavelength shifted by an interval of 10 nm or more and 160 nm or less between two light reflection layers adjacent to each other.

Abstract: A light controlling film comprises a light reflecting film and a light controlling layer that are laminated. The light reflecting film comprises at least two laminated light reflecting layers including at least one of light reflecting layers PRL-1 to PRL-3 that a central reflection wavelength of 400 nm-500 nm, 500 nm-600 nm, and 600 nm-700 nm, respectively, and a reflectance to ordinary light at the central reflection wavelength of 5%-25%. The at least two light reflecting layers have central reflection wavelengths that are different from each other. All of the at least two laminated light reflecting layers have a property of reflecting polarized light having the same orientation. The light controlling layer comprises two quarter wave plates, and the light reflecting film is laminated so as to be interposed between the two quarter wave plates.

Abstract: An optical laminate structure includes a light control laminate having at least one light reflection layer, a first quarter wave plate laminated on one of surfaces of the light reflection layer, and a second quarter wave plate laminated on another surface of the light reflection layer. The light reflection layer includes a right-handed circularly polarized light reflection layer or a left-handed circularly polarized light reflection layer, and an angle formed by a polarization axis of the S-polarized light or P-polarized light incident from a position inclined from an axis perpendicular to a surface of the light control laminate by 45° or more and 65° or less and a slow axis of the first quarter wave plate on a side to which the S-polarized light or P-polarized light is incident is 5° or more and less than 45°.

Abstract: A light reflection film including: a visible light reflection unit includes at least one visible light reflection layer having a reflection band in which a visible light average reflectance is higher than 25% and equal to or lower than 55% in part or all of a visible light range equal to or longer than 400 nm and shorter than 700 nm; and a light reflection layer PRL-1 having a central reflected wavelength of 700 nm to 950 nm inclusive and having a reflectance higher than 25% and equal to or lower than 55% to ordinary light at the central reflected wavelength. The visible light reflection layer and the light reflection layer PRL-1 both reflect polarized light in an identical direction.

Abstract: A light reflection film includes at least one light reflection layer RPRL in which a cholesteric liquid crystal phase of a right-handed helical structure having right circularly polarized light reflection ability is fixed; and at least one light reflection layer LPRL in which a cholesteric liquid crystal phase of a left-handed helical structure having left circularly polarized light reflection ability is fixed. A total of three or more layers of the light reflection layer(s) RPRL and the light reflection layer(s) LPRL are laminated. The light reflection layer(s) RPRL and the light reflection layer(s) LPRL laminated each have a selective reflection center wavelength shifted by an interval of 10 nm or more and 160 nm or less between two light reflection layers adjacent to each other.

Abstract: A light controlling film comprises a light reflecting film and a light controlling layer that are laminated. The light reflecting film comprises at least two laminated light reflecting layers including at least one of light reflecting layers PRL-1 to PRL-3 that a central reflection wavelength of 400 nm-500 nm, 500 nm-600 nm, and 600 nm-700 nm, respectively, and a reflectance to ordinary light at the central reflection wavelength of 5%-25%. The at least two light reflecting layers have central reflection wavelengths that are different from each other. All of the at least two laminated light reflecting layers have a property of reflecting polarized light having the same orientation. The light controlling layer comprises two quarter wave plates, and the light reflecting film is laminated so as to be interposed between the two quarter wave plates.