An optical scanning device , comprising: a light source (1; 1-1 to 1-3) capable of changing a wavelength or a phase of a light to be output; an optical mode converter (5; 5-1 to 5-3) connected to an optical waveguide through which the light output from the light source (1; 1-1 to 1-3) transmits, and configured to radiate the light received through the optical waveguide ; a mirror arranged around the optical mode converter (5; 5-1 to 5-3), and configured to reflect the light radiated from the optical mode converter (5; 5-1 to 5-3) and then reflected from an object , toward an optical receiver ; and an actuator having a first planar portion , a second planar portion , and a third planar portion , wherein the second planar portion has a hole in which the first planar portion is disposed, and the third planar portion has a hole in which the second planar portion is disposed, wherein the third planar portion supports the second planar portion via a first shaft , and is connected to the second planar portion via the first shaft and rotatable about the first shaft , the second planar portion supports the first planar portion via a second shaft substantially perpendicular to the first shaft , and is connected to the first planar portion via the second shaft and rotatable about the second shaft , the first planar portion holds the optical mode converter (5; 5-1 to 5-3) and the mirror , the optical mode converter (5; 5-1 to 5-3) is configured to change a radiation direction of the light to be transmitted from the optical mode converter (5; 5-1 to 5-3), in accordance with a change in wavelength of the light output from the light source (1; 1-1 to 1-3) or phase of the light output from the light source (1; 1-1 to 1-3), and the actuator is configured to rotate the first planar portion about each of the first and second shafts (7d and 7e). a light source (1; 1-1 to 1-3) capable of changing a wavelength or a phase of a light to be output; an optical mode converter (5; 5-1 to 5-3) connected to an optical waveguide through which the light output from the light source (1; 1-1 to 1-3) transmits, and configured to radiate the light received through the optical waveguide ; a mirror arranged around the optical mode converter (5; 5-1 to 5-3), and configured to reflect the light radiated from the optical mode converter (5; 5-1 to 5-3) and then reflected from an object , toward an optical receiver ; and an actuator having a first planar portion , a second planar portion , and a third planar portion , wherein the second planar portion has a hole in which the first planar portion is disposed, and the third planar portion has a hole in which the second planar portion is disposed, wherein the third planar portion supports the second planar portion via a first shaft , and is connected to the second planar portion via the first shaft and rotatable about the first shaft , the second planar portion supports the first planar portion via a second shaft substantially perpendicular to the first shaft , and is connected to the first planar portion via the second shaft and rotatable about the second shaft , the first planar portion holds the optical mode converter (5; 5-1 to 5-3) and the mirror , the optical mode converter (5; 5-1 to 5-3) is configured to change a radiation direction of the light to be transmitted from the optical mode converter (5; 5-1 to 5-3), in accordance with a change in wavelength of the light output from the light source (1; 1-1 to 1-3) or phase of the light output from the light source (1; 1-1 to 1-3), and the actuator is configured to rotate the first planar portion about each of the first and second shafts (7d and 7e). <EOS>