PURPOSE:To alleviate roughening caused in accordance with the intensity distribution of electron beam spots by using specified electron beam spots for an electron beam resist, and exposing the resist to electron beams changed in exposure amt. in accordance with exposure positions. CONSTITUTION:A positive type transparent electron beam resist 5 formed on a glass substrate 4 for constituting a micro-Fresnel lens is exposed by using electron beam spots 6 each having a diameter equal to an exposure pitch P and a beam intensity distribution of a steep mountain form, and electron beam spots 7 each having a diameter twice the pitch P and a beam intensity distribution of gentle mountain form. The same spot 7 is used at the exposure positions a2, a3, a4-, and to change exposure amt., e.g., the electron beam exposure amt. is kept constant, and scanning times are decreased in the order of the positions a2, a3, a4-. When the resist 5 is developed, the parts irradiated with the beam spots 6, 7 are dissolved off, and ring bands 5a are formed.
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