Optical instrument for identifying and localizing micro-engravings present on an ophthalmic lens, including: - a point light source; - a collimating member, said point light source being placed at a first focal point of said collimating member so that light issued from said point light source becomes, after having passed through said collimating member, a beam of collimated light; - a member for sending back light; - a holder configured to hold said ophthalmic lens between said collimating member and said member for sending back light; said collimating member, said holder and said member for sending back light are placed so that the beam of collimated light issued from said collimating member encounters the location on the ophthalmic lens where micro-engravings are present, passes through said ophthalmic lens, encounters said member for sending back light, returns toward said ophthalmic lens and once again passes through said ophthalmic lens then said collimating member; - an image-exploiting unit; and - an image-capturing unit connected to said image-exploiting unit, which image-capturing unit includes an objective placed at a second focal point of said collimating member, which objective is focused so that the images delivered to the image-exploiting unit, which is connected to said image-capturing unit, contain a representation of said micro-engravings allowing said micro-engravings to be identified and localized; characterized in that: - said member for sending back light is a backscatterer; - said objective of said image-capturing unit is focused in order to deliver to the image-exploiting unit images of the backscatterer; - said point light source has a wavelength λ comprised between 700 and 1000 nm; and - said collimating member has a focal length F and said point light source has a diameter D smaller than or equal to one fiftieth of the focal length F. - a point light source; - a collimating member, said point light source being placed at a first focal point of said collimating member so that light issued from said point light source becomes, after having passed through said collimating member, a beam of collimated light; - a member for sending back light; - a holder configured to hold said ophthalmic lens between said collimating member and said member for sending back light; said collimating member, said holder and said member for sending back light are placed so that the beam of collimated light issued from said collimating member encounters the location on the ophthalmic lens where micro-engravings are present, passes through said ophthalmic lens, encounters said member for sending back light, returns toward said ophthalmic lens and once again passes through said ophthalmic lens then said collimating member; - an image-exploiting unit; and - an image-capturing unit connected to said image-exploiting unit, which image-capturing unit includes an objective placed at a second focal point of said collimating member, which objective is focused so that the images delivered to the image-exploiting unit, which is connected to said image-capturing unit, contain a representation of said micro-engravings allowing said micro-engravings to be identified and localized; - said member for sending back light is a backscatterer; - said objective of said image-capturing unit is focused in order to deliver to the image-exploiting unit images of the backscatterer; - said point light source has a wavelength λ comprised between 700 and 1000 nm; and - said collimating member has a focal length F and said point light source has a diameter D smaller than or equal to one fiftieth of the focal length F.