Spiral scanning image recording apparatus and image recording method

An image recording method of recording an image by spirally scanning a photosensitive material, being mounted on a first major surface of a rotator continuously rotating in a main scanning direction, with a plurality of light beams being modulated by an image signal, said method comprising:

• (a) a step of arranging a light emitting unit emitting said plurality of light beams, an arrangement direction control unit being capable of inclining an arrangement direction of said plurality of light beams emitted from said light emitting unit, corresponding to an arrangement direction of an image being formed by applying said plurality of light beams onto a virtual screen, with respect to a subscanning direction being perpendicular to said main scanning direction, and an imaging unit, being variable in magnification, for imaging said plurality of light beams being inclined in arrangement by said arrangement direction control unit on said photosensitive material, on a second major surface of an exposure head having said second major surface and being movable in said subscanning direction;
• (b) a step of preparing a memory unit storing said image signal;
• (c) a step of inputting an input signal commanding resolution corresponding to a number of exposure pixels, to be imaged on said photosensitive material, to be included per unit length in an arrangement direction thereof;
• (d) a step of setting a magnification value corresponding to said resolution in said imaging unit on the basis of said input signal;
• (e) a step of electrically deciding an inclination angle, corresponding to an intersection angle between said arrangement direction of said plurality of light beams and said subscanning direction, and a moving speed of said exposure head, said inclination angle and said moving speed corresponding to said resolution, on the basis of said input signal for generating first and second control signals providing said inclination angle and said moving speed respectively;
• (f) a step of controlling said arrangement direction control unit for inclining said arrangement direction of said plurality of light beams with respect to said subscanning direction at said inclination angle on the basis of said first control signal;
• (g) a step of moving said exposure head in said subscanning direction at said moving speed on the basis of said second control signal;
• and
• (h) a step of reading said image signal from said memory unit and applying said image signal to said light emitting unit every rotation of said rotator, thereby scanning said photosensitive material with modulated said plurality of light beams.