AUTHORS: Sang-Young Cho
Download as PDF
An interactive whiteboard can either be a standalone computer with touchscreen or a large functioning touchpad for computer display. Interactive whiteboard systems with laser optic modules can overcome the high cost, low resolution, and low scalability of large touchscreens. Recently, a trigonometric method to find the positions of laser optic modules has been suggested to install the whiteboard system with the laser optic module. The method calculates the geometrical positions of laser optic modules using the sensed angle values of the three touched points on a whiteboard display. Three patterns of touched points are used and trigonometric expressions are derived for each pattern. This paper derived trigonometric expressions that generalize the expressions for three different patterns. Using the derived expressions, we showed that the expression set for each pattern is a special case of the generalized trigonometric expression set.
KEYWORDS: Interactive whiteboard, Touchscreen, Calibration, Trigonometric, Locating problem
REFERENCES:
[1] J. Dostal, Reflections on the Use of Interactive
Whiteboards in Instruction in International
Context, The New Educational Review, Vol.
25, No. 3, 2011, pp. 205-220.
[2] G. Walker, A Review of Technologies for
Sensing Contact Location on the Surface of a
Display, Journal of the Society for Information
Display, Vol. 20, No. 8, 2012, pp. 413-440.
[3] A. Holzinger, Finger Instead of Mouse: Touch
Screens as a Means of Enhancing Universal
Access, LNCS, Vol. 2615, 2003, pp. 387-397.
[4] C. J. William and H. S. George, Discriminating
Contact Sensor, U.S. Patent 3911215A, 1975.
[5] G Barrett and R. Omote, Projected-Capacitive
Touch Technology, International Display
Magazine, Vol. 26, No. 3, 2010, pp. 16-21.
[6] K. North and H. D’Souza, Acoustic Pulse
Recognition Enters Touch-Screen Market,
Information Display, Vol. 22, No. 12, 2006, pp.
22-25.
[7] A. Butler, S. Izadi, and S. Hodges, Side Sight:
Multi-Touch Interaction around Small Devices,
in 21st Annual ACM Symposium User Interface
Software Technology, 2008, pp. 201-204.
[8] G. Walker, Camera-Based Optical Touch
Technology, Information Display, Vol. 26, No.
3, 2010, pp. 30-34.
[9] A. Nathan and S. Gao, Interactive Displays:
The Next Omnipresent Technology, Proc. Of
the IEEE, Vol. 104, No. 8, 2016, pp. 1503-
1507.
[10] W.Grussenmeyer and E. Folmer, Accessible
Touchscreen Technology for People with
Visual Impairments: A Survey, ACM
Transactions on Accessible Computing, Vol. 9,
No. 2, 2017, Article 6 p31.
[11] S. Chun and I.-S. Koo, Beam Projector
Calibration System Based on Zigbee, The
Journal of the Institute of Internet,
Broadcasting and Communication, Vol. 11,
No. 2, 2011, pp. 13-19.
[12] S.-Y. Cho, Mathematical Methods to Locate
Touch Points Using Laser Optic Modules,
International Journal of Circuits, Systems and
Signal Processing, Vol. 12, 2018, pp. 229-234.
