The inside of the eVO 500D slit lamp with touchscreen display consists of robust die-cast aluminium components, while its outside is completely covered in plastic. This prevents the housing from heating up and thus enables the ophthalmologist to safely touch the device in order to adjust the light angle. All controls are integrated in the base, which enhances user convenience. The width of the light slit can be marked via a scale on the respective control knob. The image capture function is controlled via a joystick integrated in the base.