Laser marker

A laser marker comprising:

• a base comprising:
• a first guide portion;
• and
• a restriction part;
• a laser oscillator configured to emit laser light, the laser oscillator being removably mounted to the base by sliding in a mounting direction and being placed on the base, the laser oscillator comprising:
• a second guide portion extending in the mounting direction, the second guide portion being configured to be engaged with the first guide portion;
• a contact part configured to be in contact with the restriction part in a case the laser oscillator is mounted to the base;
• and
• an expander;
• and
• a scanner having an insertion part, the expander being inserted into the insertion part in a case the laser oscillator is mounted to the scanner, and the scanner being configured to scan the laser light emitted from the laser oscillator,
• wherein the first guide portion comprises:
• an upstream-side first guide portion located upstream of the base in the mounting direction;
• and
• a downstream-side first guide portion located downstream of the upstream-side first guide portion in the mounting direction, and
• wherein the second guide portion comprises:
• an upstream-side second guide portion located on upstream of the mounting direction;
• and a downstream-side second guide portion located on downstream of the upstream-side second guide portion in the mounting direction, and
• wherein the upstream-side second guide portion comprises a first slit,
• wherein the downstream-side second guide portion comprises a second slit,
• wherein the upstream-side second guide portion and the downstream-side second guide portion have a closed end closed on an inner side of the laser oscillator and an open end opened on an outer side of the laser oscillator,
• wherein a first distance is equal to or greater than a second distance, the first distance being a distance between sides, which face each other, of the upstream-side first guide portion and the downstream-side first guide portion of the base, the second distance being a distance between the closed end of the upstream-side second guide portion and the open end of the downstream-side second guide portion of the laser oscillator,
• wherein the first distance is smaller than a third distance, the third distance being a distance between the open ends of the upstream-side second guide portion and the downstream-side second guide portion of the laser oscillator, and
• wherein a fourth distance is greater than a fifth distance, the fourth distance being a distance, in the mounting direction, between an upstream side of the insertion part and an upstream side of the downstream-side first guide portion, the fifth distance being a distance, in the mounting direction, between a tip end of the expander and the open end of the downstream-side second guide portion of the laser oscillator.