In order to achieve improved dose control, a device for irradiating an object having an optically observable property is provided. The device includes an applicator for irradiating the object, and a detector system that is configured to capture light being emitted from an irradiated region and, based thereon, to generate a detector signal. A processor unit is configured to calculate a value for the property based thereon and, based on the calculated value, to determine a dose for the irradiation.
