A see-through type display apparatus comprising: a see-through type optical system configured to transmit a first image via a first-path light, which is light traveling on a first path, to an ocular organ of a user to increase a viewing angle of the first image, and second image via a second-path light, which is light traveling on a second path, to the ocular organ of the user; and an incident light-dependent lens unit provided between the see-through type optical system and the ocular organ of the user and having different refractive powers according to the polarization direction of incident light; wherein the incident light-dependent lens unit has a positive first refractive power with respect to the first-path light and has a second refractive power with respect to the second-path light, and the second refractive power is different from the first refractive power; wherein the incident light-dependent lens unit comprises a first lens having a focal length that varies according to polarization directions of the incident light and a second lens joined adjacent to the first lens and having a constant focal length regardless of the polarization directions of the incident light; and a transparent image forming device configured to form the first image and comprising a two-dimensional array of pixels, each pixel having a light-emitting element; wherein the second image is an external image that the user faces through the see-through type display apparatus; characterized by: a polarizer facing the incident light-dependent lens unit with the transparent image forming device interposed between the polarizer and the incident light-dependent lens unit; wherein the transparent image forming device is further characterized in that: a polarization layer is provided at an exit surface of each light emitting element for polarizing the emitted light in a direction orthogonal to the direction of polarization of the polarizer; each light-emitting element has a transparent pixel region around it; wherein the second image is transmitted through the transparent pixel regions around the light-emitting elements of the transparent image forming device to the ocular organ of the user. a see-through type optical system configured to transmit a first image via a first-path light, which is light traveling on a first path, to an ocular organ of a user to increase a viewing angle of the first image, and second image via a second-path light, which is light traveling on a second path, to the ocular organ of the user; and an incident light-dependent lens unit provided between the see-through type optical system and the ocular organ of the user and having different refractive powers according to the polarization direction of incident light; wherein the incident light-dependent lens unit has a positive first refractive power with respect to the first-path light and has a second refractive power with respect to the second-path light, and the second refractive power is different from the first refractive power; wherein the incident light-dependent lens unit comprises a first lens having a focal length that varies according to polarization directions of the incident light and a second lens joined adjacent to the first lens and having a constant focal length regardless of the polarization directions of the incident light; and a transparent image forming device configured to form the first image and comprising a two-dimensional array of pixels, each pixel having a light-emitting element; wherein the second image is an external image that the user faces through the see-through type display apparatus; characterized by: a polarizer facing the incident light-dependent lens unit with the transparent image forming device interposed between the polarizer and the incident light-dependent lens unit; wherein the transparent image forming device is further characterized in that: a polarizer facing the incident light-dependent lens unit with the transparent image forming device interposed between the polarizer and the incident light-dependent lens unit; wherein the transparent image forming device is further characterized in that: a polarization layer is provided at an exit surface of each light emitting element for polarizing the emitted light in a direction orthogonal to the direction of polarization of the polarizer; each light-emitting element has a transparent pixel region around it; wherein the second image is transmitted through the transparent pixel regions around the light-emitting elements of the transparent image forming device to the ocular organ of the user.