1. Field of the Invention
The present invention relates to a surface emitting laser, a surface emitting laser array, and an optical apparatus having the surface emitting laser array.
2. Description of the Related Art
A vertical-cavity surface-emitting laser (VCSEL), by which it is easy to form a two-dimensional array as an exposure light source for forming a latent image on a photoreceptor as a scanning surface, is used for a scanning optical apparatus in an electrophotographic image forming apparatus for use in a laser beam printer or a digital copier.
An example of an optical system of an image forming apparatus using a surface emitting laser is disclosed in Japanese Patent Application Laid-Open No. 2008-052197. According to Japanese Patent Application Laid-Open No. 2008-052197, a surface emitting laser having a plurality of light emitting points is used as a multi-beam laser light source. In order to limit the light beam width of a light beam emitted from the light source and to form the beam into a desired beam shape, the optical system has an aperture stop common to each laser light source. The formed beams are deflected and scanned by an optical deflector and imaged in a spot shape on a photoreceptor drum surface as a scanning surface by an imaging optical system.