A light emitting unit (2) for emitting a CD-use semiconductor laser beam (4) and a DVD-use semiconductor laser beam (5), wherein, when the width of an angle formed by lines formed by connecting points, in a plane parallel to the pn junction surface of a semiconductor, where a laser radiation strength is 1/2 the strength at the center of the laser is defined as the radiation angle width of a laser, the radiation angle width ?2 of the DVD-sue laser beam (5) is set to be at least 1.3 times the radiation angle width ?1 of the CD-use laser beam (4).