1. Introduction

When designing and building digital classrooms, there are several important details that should be addressed at the first stage. The room should work properly for all categories of users, i.e. the teacher, students present in the room and students participating on videoconference at the far end part. One of the most important and critical tasks is to define the level of usage of the digital classroom, see the next section.

Generally, it is more complicated to design and more expensive to build classrooms with a high level of usage. In addition, digital classrooms will often have combined levels of usage, with some usage in two of the levels or, perhaps, all three

Choice of equipment and the room's functionality will be influenced by the following factors:

• Definition of the room's primary and secondary level of usage.
• How many people will be using the rooms and the systems?
• Who will operate and maintain the equipment: teachers, local super users or suppliers?
• The room size (length, width, height), number of, and placement of, windows, geo-graphical orientation etc. This will influence the choice of monitors and projecting sur-faces, speakers and microphone systems.
• The acoustic properties of the room.
• The light conditions of the room.
• Colours used on walls and fabrics, and colours on furniture.

One should try to achieve flexible solution with respect to 1) furnishing and 2) size of projecting surfaces and monitors, so that both big and small groups feel comfortable with the solutions. Apparent eye contact with far end parts is achieved by looking straight into the camera. The placement of cameras with respect to monitors is therefore critical. As a general requirement, the camera must be placed as near the monitor of far end part as possible. It is decisive for the level of involvement and inclusion of course participants that the instructor looks directly into the camera most of the time. An example: Think about the newsreader on TV. When he is looking into the camera, we may feel that he is telling us something rather than just reading a paper to us (which he actually does).

For small rooms, monitors should not be too large, because you will then look far away from the camera when you are looking at the monitor where you see the far end part(s). In large rooms it is recommendable to use more than one camera/monitor system or projecting surface, to ensure good quality for different sizes of groups.