Multiple spot size optical profilometer, ellipsometer, reflectometer and scatterometer

A system for measuring a surface of an object comprising:

• a first electromagnetic signal source for transmitting a first signal toward a first position on the object;
• a magnification unit, disposed to receive said first electromagnetic signal, for magnifying said first electromagnetic signal by a magnification factor to modify a beam diameter of said first electromagnetic signal wherein said magnification factor is modifyable;
• a first lens, for focusing said magnified first electromagnetic signal on said first position on said object, said size of said first position dependent upon said magnification factor;
• a position sensitive detector, receiving a portion of said magnified first electromagnetic signal after reflecting from said first object, for generating a first output signal;
• a processor, receiving said first output signal, for generating a characteristic signal representing at least one of a height of said first position, a slope of said first position, an index of refraction at said first position, and thickness of a layer on said first object.