From: Vangelis Pappas-Katsiafas <>
To: Steve Jobs <>
Sent: Wednesday, December 5, 2007 9:56:38 PM
Subject: Re: Cylinder visualisation of date in iPhone calendar


Thank you very much for your reply.

- The gambling machine wheel does not map any time series or time points on its periphery, just some items.

In my thesis I am talking about explicitly mapping time series on the periphery of the wheel/cylinder, please see excerpt  below.

Anyhow, do you see any scope for collaboration (of some kind) in the UI / visualisation area? There are more (3D) visual metaphors beyond the wheel. Can I contribute to the success of Apple?

Kind regards,


Excerpt from my thesis about the 'cylinder' visualisation method:
...the instances of each time varying value are placed in a single column. The value instances over a time period can be viewed by rotating the cylinder around its axis. The correspondent to ‘NOW’ time point, textual tuple is positioned along the facet closer to the viewer, which is the most distinguished due to the perspective projection and the photorealistic rendering."

----- Original Message ----

From: Steve Jobs <>
To: Vangelis Pappas-Katsiafas <>

Sent: Wednesday, December 5, 2007 7:23:30 PM
Subject: Re: Cylinder visualisation of date in iPhone calendar

The wheel we modeled our UI after has been used on gambling machines for decades.





On Dec 5, 2007, at 8:55 AM, Vangelis Pappas-Katsiafas wrote:

Dear Steve,

I would like to draw your attention to a visualisation method that I have published in 1995 as my academic thesis in the University of Manchester
Institute od Science and Technology, UK. It's about the visualisation of text (and particular temporal associated text) using a cylinder and I think the date chooser control in the iPhone calendar is looking extremely similar to my method.
My method is also illustrated and exemplified in the following URL, as well as my thesis.
(The cylinder method)

I also present below here a brief comparison between my method and the iPhone calendar date choice 3D control. Admittedly, the iPhone control is more polished and visually pleasing (congratulation for that!), but the concept is the same; my drawings are just an early examplification of the visualisation method.

I would like to have some form of recognition for my work and/or explore any way of exploiting these ideas and intellectual property in common.
I would like to note that I have the full backing of the University of Manchester and my supervisor Dr Babis Theodoulidis for communicating with you via this email. I would also like to express my admiration of the innovative and daring attitude of apple computers during the course of its existence.

Kind regards,

Evangelos (Vangelis) Pappas-Katsiafas

P.S. I have also posted a similar message to



The new iphone calendar widget to choose a date (2007)



Vangelis proposed cylinder visualisation method in 1995 (University of Manchester Institute of Science and Technology thesis):

also an example of a font list control which can replace a conventional 2D combo box: