Patent ID: 8279516

Claim:
A wavelength conversion device that performs a wavelength shift amount Δλ of wavelength shifting with respect to an incident light beam, the device comprising: a first wavelength converter that comprises: an optical amplifier that amplifies the incident light beam and generates an amplified light beam; a first dispersion flat fiber that spreads the wavelength spectrum width of the amplified light beam and generates a first fiber output light beam; and a first wavelength filter that transmits a predetermined wavelength bandwidth of the first fiber output light beam and generates a first wavelength converted light beam, a center wavelength of the first wavelength converted light beam being shifted by a first wavelength shift amount Δλ 1 from a center wavelength of the incident light beam; and a second wavelength converter that does not include an optical amplifier and comprises: a second dispersion flat fiber that spreads the wavelength spectrum width of the first wavelength converted light beam and generates a second fiber output light beam; and a second wavelength filter that transmits a predetermined wavelength bandwidth of the second fiber output light beam and generates a second wavelength converted light beam, a center wavelength of the second wavelength converted light beam being shifted by a second wavelength shift amount Δλ 2 from the center wavelength of the first wavelength converted light beam; wherein the first wavelength shift amount Δλ 1 and the second wavelength shift amount Δλ 2 satisfy the conditions Δλ 1 +Δλ 2 =Δλ, Δλ 1 ×Δλ 2 <0, and |Δλ 1 |<|Δλ 2 |.