The useability and wearing comfort of a head-mounted display can be improved by providing an air conditioning device and a mechanism to control the temperature and humidity of the air surrounding the face of a wearer and of the face in correspondence to measurements of the properties of the air being in direct proximity to the user's head resulting in a reduction of the negative effects of wearing a head-mounted display device in general, and in particular in situations of increased physical activity of the user or/and in situations with changing properties of the surrounding air. In one example, a user can wear the head-mounted display device without having the facial skin producing extra moisture, and in this way without occurring condensation on a part of the head-mounted display device, specifically without fogging up the screen of the head-mounted display device. If a head-mounted display device is able to measure the conditions of the air in direct proximity of the user's head, then the control system of the device can alter the properties of the air in response to the changed control parameters. Different parameters can be measured to control the device and different ways of conditioning the air can be applied.