Patent ID: 8614844

Claim:
An optical scanning apparatus, comprising: a light source that emits a beam of light; and a scanning device that scans the beam of light in two axial directions that are substantially perpendicular to each other at a first frequency f H and a second frequency f L , wherein the first frequency f H and the second frequency f L have relations determined according to following Mathematical Formulas 1 to 4 or following Mathematical Formulas 5 to 8: f H = N × f L ± 1 2 ⁢ ( 2 ⁢ a + 1 ) ⁢ f L ( 2 ⁢ a + 1 ) ⁢ P - b , [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 1 ] a = 1 , 2 , 3 , … ⁢ ⁢ and ⁢ ⁢ a max = [ 1 4 ⁢ ( f L Fr 2 - 3 ) ] , [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 2 ] b = ± 1 , ± 2 , … ⁢ , a , and [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 3 ] P = [ 1 4 ⁢ ( 2 ⁢ a + 1 ) ⁢ ( f L Fr 2 + 4 ⁢ b + 1 ) ] , [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 4 ] in the Mathematical Formulas 1 to 4, “a” is an arbitrary integer having a maximum value a max , N is a positive integer, Fr is a frame rate, [ ] represents a Gauss symbol, and a=b=0 is included as a special case: f H = N × f L ± 2 ⁢ af L 4 ⁢ aP - ( 2 ⁢ b + 1 ) , [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 5 ] a = 1 , 2 , 3 , … ⁢ ⁢ and ⁢ ⁢ a max = [ 1 4 ⁢ ( f L Fr 2 - 1 ) ] , [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 6 ] b = - a , - a + 1 , … ⁢ , a - 1 , and [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 7 ] P = [ 1 4 ⁢ ( 2 ⁢ a ) ⁢ ( f L Fr 2 + 4 ⁢ b + 3 ) ] , [ Mathematical ⁢ ⁢ Formula ⁢ ⁢ 8 ] in the Mathematical Formulas 5 to 8, “a” is an arbitrary integer having a maximum value a max , “b” is an integer within a range of −a to a−1, N is a positive even number, Fr is the frame rate, and [ ] represents the Gauss symbol.