Abstract: The present invention provides a wafer-scale lens in which a total optical length is short in comparison with an image height and astigmatism and other aberrations can be well corrected, and an optical system in which a lens element closest to the object side is thin in thickness. The optical system includes a first lens that is disposed closest to the object side and is positive in refractive power; a second lens that is disposed on the image side and has a concave surface on the object side; an i-th lens, (i?3), that is disposed closest to the image side in lenses disposed on the image side and includes an i-th lens plate and a lens element which is formed on at least either the object side surface or the image side surface of the i-th lens plate, and has a refraction index different from the i-th lens plate and positive or negative refractive power; and satisfies 0.9>Ymax/Y>0.

Abstract: An imaging lens (LN) includes at least one lens block (BK), and an aperture stop (ape). The lens block (BK) includes parallel flat lens substrates (LS) formed of different materials, and a lens (L). In the imaging lens (LN), a first lens block (BK1) positioned closest to an object includes a first lens substrate (LS1) and a lens (L[LS1o], and a prescribed conditional expression is satisfied.

Abstract: An imaging lens (LN) includes one or two lens blocks (BK), and an aperture stop (ape). The lens block (BK) includes a plane-parallel lens substrate (LS) and a lens (L) formed of different materials. In the imaging lens (LN), a first lens block (BK1) disposed at the most object-side exerts a positive optical power, and a conditional formula defined by the absolute difference between the index of refraction of a first lens substrate (LS1) and the index of refraction of a lens (L[LS1o]) contiguous with an object-side substrate surface of the first lens substrate (LS) is fulfilled.

Abstract: An imaging lens (LN) includes at least one lens block (BK), and an aperture stop (ape). The lens block (BK) includes parallel flat lens substrates (LS) formed of different materials, and a lens (L). In the imaging lens (LN), a first lens block (BK1) positioned closest to an object includes a first lens substrate (LS1) and a lens (L[LS1o], and a prescribed conditional expression is satisfied.

Abstract: An imaging lens (LN) includes one or two lens blocks (BK), and an aperture stop (ape). The lens block (BK) includes a plane-parallel lens substrate (LS) and a lens (L) formed of different materials. In the imaging lens (LN), a first lens block (BK1) disposed at the most object-side exerts a positive optical power, and a conditional formula defined by the absolute difference between the index of refraction of a first lens substrate (LS1) and the index of refraction of a lens (L[LS1o]) contiguous with an object-side substrate surface of the first lens substrate (LS) is fulfilled.

Abstract: Provided is an imaging lens using a wafer scale lens which can easily be produced in a mass production. The entire optical length can be reduced without increasing a lens substrate or a lens formed on the substrate or without using a diffracting plane. The aberration can be preferably corrected. The imaging lens forms a first lens having a positive refractive power and Abbe number v1 on the object side and a second lens having a negative refractive power and Abbe number v2 on the image side of the first lens substrate. The difference between the Abbe number v1 and the Abbe number (v1?v2) is set to be a value greater than 10.