Method for assessing irradiation intensity of a laser beam, an apparatus for assessing irradiation intensity used under this method, and a laser beam irradiation system

An apparatus for assessing irradiation intensity of a laser beam comprising:

• a reference object on which a change in its state is caused by irradiating the laser beam, and a light quantity of transmitted light of specified illumination light changes in accordance with an irradiation energy density of the laser beam when the illumination light is projected;
• an image obtaining device which obtains an image formed by a change in the light quantity of the transmitted light, occurring when the illumination light is projected on the reference object having been irradiated by the laser beam;
• and
• an analyzing device which analyzes a condition of the change in the reference object based on the obtained image, wherein an irradiation intensity distribution of the laser beam is assessed based on an analytical result.

A laser beam irradiation system comprising:

• an irradiation optical system for irradiating a laser beam onto an object to be irradiated;
• a reference object on which a change in its state is caused by irradiating the laser beam, and a light quantity of transmitted light of specified illumination light changes in accordance with an irradiation energy density of the laser beam when the illumination light is projected;
• an image obtaining device which obtains an image formed by a change in the light quantity of the transmitted light, occurring when the illumination light is projected on the reference object having been irradiated by the laser beam;
• an analyzing device which analyzes a condition of the change in the reference object based on the obtained image;
• and
• a control device which obtains control data for the system so that the object to be irradiated achieves a condition of a desired change based on an analytical result from the analyzing device.