Abstract: A head-up display device includes: an image generator that emits light; and a display member including: a projection surface onto which the light is projected, wherein when the light is emitted to the projection surface, the light is reflected from the projection surface to display a real image passing through the display member and a virtual image; and a plate material including: a pair of optical surfaces, one positioned nearer to an observer side than the other, and either of which can serve as the projection surface; an end surface connecting peripheries of the pair of optical surfaces; and an end main surface formed at a predetermined a distance from the end surface to a reference line passing through a reference point and being orthogonal to a tangent plane at the reference point.

Abstract: A head-up display device includes: an image generator that emits light; and a display member including: a projection surface onto which the light is projected, wherein when the light is emitted to the projection surface, the light is reflected from the projection surface to display a real image passing through the display member and a virtual image; and a plate material including: a pair of optical surfaces, one positioned nearer to an observer side than the other, and either of which can serve as the projection surface; an end surface connecting peripheries of the pair of optical surfaces; and an end main surface formed at a predetermined a distance from the end surface to a reference line passing through a reference point and being orthogonal to a tangent plane at the reference point.

Abstract: A light flux from the first light source forms a converged spot on first optical information recording medium by only a refraction action of the aspheric surface, or by a combination of the refraction action and an optical action given by at least one of the first phase structure and the second phase structure, a light flux from the second light source forms a converged spot on second optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure, and a light flux from the third light source forms a converged spot on third optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure.

Abstract: A first phase structure corrects at least one of a spherical aberration due to a difference between a protective substrate thickness t1 and a protective substrate thickness t2 and a spherical aberration due to a difference between a first wavelength ?1 and a second wavelength ?2, and a second phase structure corrects at least one of a spherical aberration generated when the first wavelength ?1 is changed in a range of ±10 nm, a best image point movement generated when the first wavelength ?1 is changed in a range of ±10 nm, and a spherical aberration generated when environmental temperature is changed.

Abstract: A light flux from the first light source forms a converged spot on first optical information recording medium by only a refraction action of the aspheric surface, or by a combination of the refraction action and an optical action given by at least one of the first phase structure and the second phase structure, a light flux from the second light source forms a converged spot on second optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure, and a light flux from the third light source forms a converged spot on third optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure.

Abstract: An objective lens for use in an optical pickup apparatus for recording and/or reproducing information on a first optical information recording medium having a protective substrate with a thickness t1 using a light flux with a wavelength ?1, on a second optical information recording medium having a protective substrate with a thickness t2 using a light flux with a wave length ?2 and a third optical information recording medium having a protective substrate with a thickness t3 using a light flux with a wavelength ?2, the objective lens includes: an optical surface including a central area and a peripheral area, wherein when the objective optical lens forms the portion of the light flux with the wavelength ?2 passed the central area into a converged spot through a substrate with a thickness t4, the objective optical lens makes a spherical aberration of the converged spot a minimum value.

Abstract: A light flux from the first light source forms a converged spot on first optical information recording medium by only a refraction action of the aspheric surface, or by a combination of the refraction action and an optical action given by at least one of the first phase structure and the second phase structure, a light flux from the second light source forms a converged spot on second optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure, and a light flux from the third light source forms a converged spot on third optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure.

Abstract: An objective optical element for use in an optical pickup apparatus for recording and/or reproducing information on first—third optical information recording media using first—third light fluxes respectively, includes: a first phase structure for compensating a deterioration in a performance forming the converged spot on the information recording surface of the first optical information recording medium caused by an temperature change, a second phase structure for reducing a spherical aberration based on a thickness difference between the protective substrates of the first and second optical information media or the a wavelength difference between the first and second wavelengths, and a third phase structure for reducing a spherical aberration based on a thickness difference between the protective substrate of the first and third optical information media.

Abstract: An optical pickup apparatus is provided with a light source device to emit selectively an ordinary polarized light ray and an extraordinary polarized light ray by controlling a polarization condition of a light flux having a wavelength of ?1; and a light converging optical system. An objective lens has a phase structure made of a doubly refracting medium in which an ordinary ray refractive index no for the ordinary polarized light ray is different from an extraordinary ray refractive index ne (ne?no) for the extraordinary polarized light ray so that the phase structure has a function for not changing a transmitted wavefront of an incident light ray being one of the ordinary polarized light ray and the extraordinary polarized light ray and for changing a transmitted wavefront of an incident light ray being the other one of the ordinary polarized light ray and the extraordinary polarized light ray.

Abstract: An optical pickup apparatus is provided with a light source device to emit selectively an ordinary polarized light ray and an extraordinary polarized light ray by controlling a polarization condition of a light flux having a wavelength of ?1; and a light converging optical system. An objective lens has a phase structure made of a doubly refracting medium in which an ordinary ray refractive index no for the ordinary polarized light ray is different from an extraordinary ray refractive index ne(ne?no) for the extraordinary polarized light ray so that the phase structure has a function for not changing a transmitted wavefront of an incident light ray being one of the ordinary polarized light ray and the extraordinary polarized light ray and for changing a transmitted wavefront of an incident light ray being the other one of the ordinary polarized light ray and the extraordinary polarized light ray.

Abstract: A first phase structure corrects at least one of a spherical aberration due to a difference between a protective substrate thickness t1 and a protective substrate thickness t2 and a spherical aberration due to a difference between a first wavelength ?1 and a second wavelength ?2, and a second phase structure corrects at least one of a spherical aberration generated when the first wavelength ?1 is changed in a range of ±10 nm, a best image point movement generated when the first wavelength ?1 is changed in a range of ±10 nm, and a spherical aberration generated when environmental temperature is changed.

Abstract: A light flux from the first light source forms a converged spot on first optical information recording medium by only a refraction action of the aspheric surface, or by a combination of the refraction action and an optical action given by at least one of the first phase structure and the second phase structure, a light flux from the second light source forms a converged spot on second optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure, and a light flux from the third light source forms a converged spot on third optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure.

Abstract: An objective optical element for use in an optical pickup apparatus for recording and/or reproducing information on first—third optical information recording media using first—third light fluxes respectively, includes: a first phase structure for compensating a deterioration in a performance forming the converged spot on the information recording surface of the first optical information recording medium caused by an temperature change, a second phase structure for reducing a spherical aberration based on a thickness difference between the protective substrates of the first and second optical information media or the a wavelength difference between the first and second wavelengths, and a third phase structure for reducing a spherical aberration based on a thickness difference between the protective substrate of the first and third optical information media.

Abstract: An objective lens for use in an optical pickup apparatus for recording and/or reproducing information on a first optical information recording medium having a protective substrate with a thickness t1 using a light flux with a wavelength ?1, on a second optical information recording medium having a protective substrate with a thickness t2 using a light flux with a wave length ?2 and a third optical information recording medium having a protective substrate with a thickness t3 using a light flux with a wavelength ?2, the objective lens includes: an optical surface including a central area and a peripheral area, wherein when the objective optical lens forms the portion of the light flux with the wavelength ?2 passed the central area into a converged spot through a substrate with a thickness t4, the objective optical lens makes a spherical aberration of the converged spot a minimum value.