Digital Sundial

Hines Digital Sundial

 

 

US Patent 4,782,472

 

Recognized by the North American Sundial Society as

“The first true digital sundial”

 

     The world’s first digital sundial was invented by Steve Hines in 1984, patented in 1988, and shows the time with a true 7-segment numerical display.  The sun shines through slits in the encoder, onto the ends of optical fibers, that route the light to the 7-segment numerals in the display.

 

 

What is a 7-Segment Display?https://www.hineslab.com/wp-admin/options-general.php

     A 7-segment display is a readable number made of seven lines.  

     In the digital sundial, optical fibers from the encoder, are clear epoxied to the backs of the seven Plexiglas segments in the numerical display.  Each segment can have more than one optical fiber glued to the back.

 

      3D-printed shadow-mask sundials appeared in approximately 2015, 31 years after the 1984 Hines’ digital sundial, and do not use actual 7-segment numerals.  The Hines’ Digital Sundial is the first true digital sundial with 7-segment numerals.  

 

 

Construction:

 

      Optical fibers are epoxied in holes in the clear Plexiglas encoding cylinder (the gnomon of analog sundials). The opposite ends of the fibers are clear epoxied to backs of the segments, in the numerical display.   

 

 

   

Sunlight shines through slits in the encoder, onto the ends of optical fibers as the sun moves across the sky. 

x

x

x

x

x

A time-lapse video of the opposite end of the optical fibers that illuminate segments of the display to form readable numbers.  Most of the segments can be lighted with more than one optical fiber.

 

 

The four categories of timekeeping devices:

     All timekeeping devices fall into one of four categories, analog or digital clocks, or analog or digital sundials.  Many analog sundials are used as yard ornaments without regard to the latitude.  The digital sundial category has gone without an example for 3,600 years until the Hines’ digital sundial in 1984, and is recognized by the North American Sundial Society and Wikipedia, one Siri the first true digital sundial.  

 

 

 

The sundial in a museum:

 

 

 

 

 

 

 

 

 

print → web

 

    The digital sundial in a museum setting where visitors can rotate a “sun” handle around a globe, to sequence the overhead “sunlight” which shines through slits in the encoder to illuminate various optical fibers which illuminate segments of the 7-segment numerals.

 

 

Advantages of the Hines digital sundial over other other sundials: 

  • It provides the time at a glance.  
  • The display can be at any convenient distance hundreds or thousands of feet from the encoding cylinder.  
  • The time is displayed in 10-min. increments.
  • This is the world’s first optical A-to-D converter. Previous A-to-D converters have been electronic.  

 

 

 

Advantage of the Hines digital sundial over other timekeeping devices of any type:

  • A digital clock without electrical power.  

 

 

Sundial Resources:

 

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How it works:

 

      As the sun moves across the sky, sunlight shines through slits in the top of the encoding cylinder and sweeps over the ends of optical fibers in the bottom of the cylinder to illuminate the segments of the numerals.  The following animations are without any phase relationship.

 

 

Tens-of-hours

(Xx:xx)

Hours

(xX:xx)

Tens-of-minutes

(xx:Xx)

Minutes

(xx:xX)
A single opening in the top of the cylindrical encoder illuminate two fibers, from 10:00 AM to 12:59 PM, to form the “1”.

A one-hour-wide band of light sweeps across the ends of fibers between 9 AM and 4 PM.

 

 Light shines through different slits to sweep over this fibers to repeat the 0-1-2-3-4-5 sequence for the tens-of-minutes numeral.   The Digital Sundial reads in the smallest available digital increment above 2 minutes, with the units-minutes fixed at “0”.

 

 

 

Blueprints:

 

      Blueprints to build one 4″-diameter cylinder digital sundial are available for $200.  Please send an email or text message for the address to send your payment.

 

 


YouTube video

 

 

Activity:

  • Siri, Alexa and Google describe the Hines’ Sundial as “the world’s first digital sundial”, as of Feb. 2025.
  • “Great design“, Jean-Baptiste Rouquier, Dec. 27, 2022
  • plans ordered by Edgar Kogler, April 24, 2018
  • North American Sundial Society (NASS) declares it “The First True Digital Sundial“, October 2, 2014
  • plans ordered by Pat O’Grady, Sept. 4, 2014
  • plans ordered by Bret Niemeyer, June 28, 2011
  • plans ordered by Punjab Engineering College, India, February 6, 2008
  • plans ordered by Charles Ashcroft, Sept. 7, 2007
  • incorporated in paper presented by Bob Kellogg, at the North American Sundial Society conference in Banff, Alberta, Canada, August 21-24, 2003
  • plans ordered by Till Liepmann, April 1, 2002
  • information requested by Sundials magazine, November 29, 2001
  • plans ordered by Hans Sassenburg, May 1, 1999
  • plans ordered by James Luttrell, January 21, 1995
  • plans ordered by William Georgian, September 23, 1994
  • plans ordered by Robert Siebert, Nov. 1, 1994
  • plans ordered by William Georgian, September 27, 1994
  • plans ordered by Robert McGrath, September 10, 1994
  • plans ordered bt Phillip Rogen, September 6, 1994
  • Solar Today Magazine, August 20, 1994 issue, p. 39
  • plans ordered by Rick Steenblik, September 18, 1988
  • U.S. Patent 4,782,472, issued to S. Hines, November 1, 1988

 

Hines’ original lab notebook entries for this invention.  
p. 38 p. 39

 

 

HinesLab

 

Virginia Beach, VA, USA

 

email: [email protected]

 

ph. 818-507-5812

 

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