Tokyo-based design studio Nendo has updated the humble ballpoint pen, with a more ergonomic design called bLen, for Japanese pen manufacturer Zebra.

Nendo made a number of small changes to the basic ballpoint pen design with the aim of creating a better writing experience for the user.

The body of the pen has been designed to be comfortable to hold in the hand for long periods of time, with a brass weight placed in the tip of the pen to lower its centre of gravity and make it more stable in the writer's grip.

"This weight allows for a smooth and gentle touch on the paper, while significantly reducing unexpected movements of pen due to the centripetal force created while writing," said the studio.

A fixing element has been placed between the cartridge and exterior body to further stabilise the pen and reduce any unnecessary movement, and an additional spring included in the retractable button push for better suspension and to reduce rattling.

The button push is wider than in a regular pen, for ease of use, and to allow enough space to include the pen specifications such as ink colour and line thickness on the top of the button.

The designers looked to professional drawing tools for this feature, which often include technical information on the top for ease of identification when swapping between pens stored in a rack.

There are six different pens with various colourways and line thickness options. bLen is currently available in three colours, red, black and blue, with two thicknesses of pen tip, 0.5 millimetres and 0.7 millimetres.

For this project Nendo focused on the various little curves and movements required to write and draw every day, rather than drawing a smooth straight line which doesn't reflect many users' experience.

"The approach of the project can be compared to designing a practical compact car that fulfils small needs of our daily lives, rather than designing an aerodynamic sports car that is best for fast and linear drives," said Nendo.

The redesign of the ballpoint pen caps off a busy year for the studio, that has seen them turn their hand to projects as various as the design of an Escher exhibition at the National Gallery of Victoria in Melbourne, cutlery with a kink for Valerie Objects, cuckoo clocks and kitchen utensils that mimic hand movements and a cheesecake.