Patent ID: 6944203

Claim:
A multimode light generating module comprising: an optical cavity constituted by a semiconductor optical amplification element having a pair of end faces, and an optical fiber including a grating having an apodized periodic refractive index distribution; and a monitor light-receiving element optically coupled to said optical cavity; wherein said grating has an asymmetric reflection spectrum having a relationship: 0.5 nm>λ 0.2 −λ p >0.1 nm where λ p is the wavelength exhibiting a maximum reflectivity, and λ 0.2 is defined by (λ 0.2 h +λ 0.2 l )/2 where λ 0.2 h is a longer one of two wavelengths exhibiting a relative reflectivity of 0.2 with respect to said maximum reflectivity, and λ 0.2 l is a shorter one of two wavelengths exhibiting a relative reflectivity of 0.2 with respect to said maximum reflectivity.