| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical information recording and reproducing head in which an error and an offset are not generated in a servo signal even when the wavelength of a laser luminous flux is changed and in which the degree of freedom of a design is high. SOLUTION: This optical information recording and reproducing head is constituted by comprising a first hologram element 27 by which a luminous flux reflected by a recording medium is split into a plurality of luminous fluxes used to detect various signals. In addition, it is constituted by comprising a light receiving means 29 provided with a plurality of light receiving parts used to receive a plurality of spots formed of the plurality of luminous fluxes divided by the first hologram element 27. In addition, it is constituted by comprising a second hologram element 51 which is arranged between the first hologram element 27 and the light receiving means, which corrects the movement of a spot position due to a chromatic aberration and by which the plurality of spots are always incident on the plurality of light receiving parts. |
