A Raman microspectrometer comprising: - a hollow-cone and point-focus lighting optical device having illumination means comprising: - a point light source, said illumination means being adapted to generate a collimated incident light beam, - an optical lens having an optical axis (8, 8') and an image focal plane, the optical lens being arranged so as to receive a cylindrical incident light beam and to form an image of the source at one point in the image focal plane, - an optical system comprising a first conical lens and a second conical lens, said optical system being placed on the optical path of the incident light beam between the illumination means and the optical lens, - the first conical lens being arranged so as to receive said collimated incident light beam and to form a hollow-cone light beam having, in a plane transverse to the beam axis, a light distribution comprising a dark central portion and a clear annular portion, - the second conical lens being arranged so as to receive said hollow-cone light beam (20, 40) of the first conical lens and to form a dark-background cylindrical light beam having, in a plane transverse to the beam axis, a light distribution comprising a dark central portion and a clear annular portion, - the optical lens being arranged so as to receive said dark-background cylindrical light beam from the second conical lens, to form a hollow-cone light beam and to focus said hollow-cone light beam to a point of micrometric size in the image focal plane, and - the hollow-cone and point-focus lighting optical device being adapted to light a sample with a hollow-cone light beam focused to a point on a sample so as to generate an optical beam reflected or backscattered by the sample, characterized in that: - said microspectrometer further comprises an optical component (7, 7') placed either in said dark central portion or in said clear annular portion of the hollow-cone lighting beam (40, 50, 60), said optical component (7, 7') being adapted to spatially separate, on the one hand, an optical beam transmitted or reflected and, in the other hand, a beam scattered by the sample, so as to form a collected scattering beam (100, 71) and to direct said collected scattering beam towards a spectrometer. - a hollow-cone and point-focus lighting optical device having illumination means comprising: - a point light source, said illumination means being adapted to generate a collimated incident light beam, - an optical lens having an optical axis (8, 8') and an image focal plane, the optical lens being arranged so as to receive a cylindrical incident light beam and to form an image of the source at one point in the image focal plane, - an optical system comprising a first conical lens and a second conical lens, said optical system being placed on the optical path of the incident light beam between the illumination means and the optical lens, - the first conical lens being arranged so as to receive said collimated incident light beam and to form a hollow-cone light beam having, in a plane transverse to the beam axis, a light distribution comprising a dark central portion and a clear annular portion, - the second conical lens being arranged so as to receive said hollow-cone light beam (20, 40) of the first conical lens and to form a dark-background cylindrical light beam having, in a plane transverse to the beam axis, a light distribution comprising a dark central portion and a clear annular portion, - the optical lens being arranged so as to receive said dark-background cylindrical light beam from the second conical lens, to form a hollow-cone light beam and to focus said hollow-cone light beam to a point of micrometric size in the image focal plane, and - the hollow-cone and point-focus lighting optical device being adapted to light a sample with a hollow-cone light beam focused to a point on a sample so as to generate an optical beam reflected or backscattered by the sample, characterized in that: - said microspectrometer further comprises an optical component (7, 7') placed either in said dark central portion or in said clear annular portion of the hollow-cone lighting beam (40, 50, 60), said optical component (7, 7') being adapted to spatially separate, on the one hand, an optical beam transmitted or reflected and, in the other hand, a beam scattered by the sample, so as to form a collected scattering beam (100, 71) and to direct said collected scattering beam towards a spectrometer.