Ressence Type 5N: The Only Mechanical Watch Perfectly Readable Underwater

Ressence is announcing the release of the Ressence Type 5N, a new example of the oil-filled Type 5 watch featuring a deep night blue dial.

Ressence Type5N

Maximising the Capabilities of the Ressence Orbital Convex System

The genesis of the Type 5N starts with the Ressence Orbital Convex System (ROCS), the unique inhouse developed (and patented) horological unit featuring an ever-changing dial that continually orbit around one another. The purpose is a more efficient way of telling time. Information is displayed on a single surface, much like words on a piece of paper, making for improved readability.

This differs than that of a traditional watch, where the hands and dial are layered on one another producing an uneven viewing plane. Composed of 142 parts, the gears in the ROCS calculates the hours, runner (90 seconds) taking only the minute as a reference from the automatic movement.

Ressence Type 5N

Perfectly Readable in the Depths of the World’s Oceans

First debuted in 2015, the Type 5 is the first mechanical watch to be perfectly readable underwater regardless of the viewing angle. A true achievement in Fine Watchmaking, the Type 5N is designed with a “water drop” dial effect in order to achieve crystal-clear dial legibility for the wearer. To accomplish this, Ressence uses applied science. Because oil and glass share very similar responses to light refraction, the eye is tricked into momentarily losing its depth perception. The result is that the watch’s dial seems ever closer, vision of it apparently unimpeded by glass at all.

The Type 5 builds upon that achievement by canceling out what is known as Total Internal Reflection. Typically, under water, a traditional diver’s watch needs to be viewed straight on in order to be read properly – otherwise refraction turns the glass into a mirror. The use of oil ensures complete legibility whatever the angle of view.

The TYPE 5N meets the requirements of ISO 6425 and is able to withstand extreme conditions. The creation of this world-proof watch was therefore not without its challenges – allowing to further position Ressence at the forefront of 21st century watchmaking. Ressence ingeniously designed a two-chamber system inside the Type 5 to keep the mechanical movement and oil separate. The lower chamber is comprised of the customized automatic movement and the upper chamber is hermetically-sealed with the ROCS display module bathing in 37.5ml of oil. As such with the two-chamber system, there is no direct mechanical link between the watch’s movement and the ROCS. To accommodate this, the Type 5N uses a magnetic transmission to tie the modules together. This is done by connecting several micro-magnets to each other and positioning them in both the oil-filled upper chamber and the dry lower chamber.

In order to compensate for oil volume fluctuation (dependent on temperature), the watch is fitted with a system of seven small bellows that expand and contract dependent on the increase and decrease of the oil’s volume. For a charming visual cue – the system is indirectly connected to the temperature gauge on the dial so the user can see a representation of the bellows capacity in action.