An erect life-size lens array having a deep focal depth is realized. The erect life-size lens array includes a first lens array, a second lens array, a third lens array, a first aperture and a second aperture, wherein when a distance between a second principal plane of the second lens and a first principal plane of the third lens is ξ1, a distance between a second principal plane of the third lens and a design image surface is ξ2, a radius of a circular hole of the aperture is ra, and a defocus amount is ξ3, the erect life-size lens array is for causing an MTF at a spatial frequency ν to become MTFtarget or more and satisfies (J1(2π·ra·((1/ξ1)+(1/ξ2))·ν·ξ3))/(π·ra·((1/ξ1)+(1/ξ2))·ν·ξ3)≧MTFtarget, where J1 is a first type first-order Bessel function.