Optical recording device, optical recording method and multi-layer disk

An optical recording device that records to a multi-layer disk having multiple recording layers, said optical recording device comprising:

• an optical pickup that selectively irradiates laser light to the recording layers via an objective lens;
• and
• a control part that performs controls in such a way as to:
• set in each of the multiple recording layers a data area where user data is recorded and a calibration area used for an intensity calibration process of the laser light for recording, including a main calibration area and at least one sub calibration area, according to a same layout that applies to all of the multiple recording layers;
• use the main calibration area to perform a first calibration process for implementing initial recording to the data area in each of the multiple recording layers one by one from a recording layer farthest away from or closest to an objective lens of an optical pickup;
• record dummy data to a remainder of the main calibration area;
• and
• use the at least one sub calibration area to perform a second calibration process for additional recording to the data area,
• wherein the control part performs controls in such a way that, when the recording layer to which data will be recorded next is referred to as a target recording layer and the recording layer to which data was recorded immediately before the target recording layer is referred to as an adjacent recording layer, and when second user data of a larger size than first user data already recorded to the data area of the adjacent recording layer will be recorded to a data area of the target recording layer, then the second user data is divided into a first block corresponding to a size of the first user data and a second block for other data, and the calibration process for the first block is performed as the first calibration process using the main calibration area, while the calibration process for the second block is performed as the second calibration process using the sub calibration area.