Multiple parallel confocal system and surface measurement method using the same

A multiple parallel confocal system comprising:

• a light source for irradiating light;
• a relay lens unit through which the light traveling toward a measuring object or the light reflected from the measuring object is passed, the relay lens unit having one or more lens for focusing the light irradiated from the light source;
• a multiple optical probe having a microlens array on which a plurality of microlenses is arranged, the microlenses into which the focused light through the relay lens unit is incident;
• and
• a photo detector for detecting the incident light reflected from the measuring object and passed through the microlenses and the relay lens unit,
• wherein a working distance between each microlens and the measuring object is increased, and a back focus determined by the focal distance of each microlens and the working distance between the microlens and the measuring object and a focus of the relay lens unit are located on the same plane, the back focus being calculated by the following expression:
• BFL=f(f+x)/x
• wherein f denotes the focal distance of each microlens and f+x denotes the distance between each microlens and the measuring object, and
• wherein an aperture is disposed on a focal plane where the focuses of the relay lens unit and the back focuses of the microlenses meet, the aperture having pinholes formed thereon.