A system for real-time monitoring of surface profile and thickness measurement of at least one thin film on at least one thin film deposition unit, said system comprising: at least one laser generating means to generate at least one laser beam, said laser beam being incident on at least one substrate in said thin film deposition unit and thereby being reflected; at least one grating array based wavefront sensor to receive said reflected laser beam as an incident beam and thereby reflect at least one diffracted beam of at least one desired order, said diffracted beam isolated by at least one iris diaphragm; at least two lenses to receive said diffracted beam and generate an array of focal spots at one or more position; at least one image capturing means to capture the image of said focal spots corresponding to said position of said focal spots; at least one data processing module adapted to receive said image from said image capturing means and configured to: measure at least one wavefront of said incident beam at one or more instants of time from said focal spot positions corresponding to at least one relative position of said array of focal spot before deposition and at any subsequent instants after deposition; and generate at least one information corresponding to said surface profile and said thickness measurement simultaneously, provided the measured area over the substrate is larger than the area over which deposition is taking place, based on said wavefront measured. at least one laser generating means to generate at least one laser beam, said laser beam being incident on at least one substrate in said thin film deposition unit and thereby being reflected; at least one grating array based wavefront sensor to receive said reflected laser beam as an incident beam and thereby reflect at least one diffracted beam of at least one desired order, said diffracted beam isolated by at least one iris diaphragm; at least two lenses to receive said diffracted beam and generate an array of focal spots at one or more position; at least one image capturing means to capture the image of said focal spots corresponding to said position of said focal spots; at least one data processing module adapted to receive said image from said image capturing means and configured to: measure at least one wavefront of said incident beam at one or more instants of time from said focal spot positions corresponding to at least one relative position of said array of focal spot before deposition and at any subsequent instants after deposition; and at least two lenses to receive said diffracted beam and generate an array of focal spots at one or more position; at least one image capturing means to capture the image of said focal spots corresponding to said position of said focal spots; at least one data processing module adapted to receive said image from said image capturing means and configured to: measure at least one wavefront of said incident beam at one or more instants of time from said focal spot positions corresponding to at least one relative position of said array of focal spot before deposition and at any subsequent instants after deposition; and measure at least one wavefront of said incident beam at one or more instants of time from said focal spot positions corresponding to at least one relative position of said array of focal spot before deposition and at any subsequent instants after deposition; and generate at least one information corresponding to said surface profile and said thickness measurement simultaneously, provided the measured area over the substrate is larger than the area over which deposition is taking place, based on said wavefront measured. <EOS>