The centre of the diffraction pattern in Fraunhofer diffraction is always

In diffraction pattern

The occurrence of diffraction pattern depends on

In single slit diffraction pattern :

In the Fraunhofer class of diffraction

In the Fraunhofer class of diffraction

For Fraunhofer diffraction to occur

In diffraction pattern the fringes are of

What are the conditions of formation of maxima and minima of diffraction fringes in Fraunhofer diffraction in a single slit?