Electromagnetic wave irradiation device and image formation apparatus

An electromagnetic wave irradiation device comprising:

• an irradiator which irradiates electromagnetic waves onto a liquid droplet which has been adhered to a recording medium;
• an irradiation controller which controls the irradiator such that the irradiator irradiates the electromagnetic waves periodically such that a frequency of an irradiation period in which the electromagnetic waves are irradiated by the irradiator is a predetermined frequency;
• and
• a time setting unit which sets a time ratio obtained by dividing a length of an irradiation time during which the electromagnetic waves are irradiated by the irradiator in the irradiation period by a length of a termination time during which the electromagnetic waves are not irradiated by the irradiator in the irradiation period to be a value greater than or equal 0.2 and less than or equal to 2.