Latest Research and News Bulletins

Omni-focus Video Camera

The eye of one sewing needle is taken through the eye of another.

This video camera is the first of its kind. The Omni-focus Video Camera is able to focus any object, near or far, with high image quality and without the cameraman physically having to move the camera optics in order to focus. The power of resolution of the image is limited only by the size of a pixel of the video camera. Even fingerprints in the image are recognizable.

Omni-Focus Video Camera News release

Comparison of Omni-focus Video Camera image (left) and ordinary video camera image (right).

Converting a laptop computer or camera phone into a 3D display

For an enlarged view, click the individual figures shown above.

Iizuka discovered that a 25-micron-thick sheet of cellophane is better at rotating the polarization direction of white light (400 to 700 nm) than a half-waveplate designed for a specific wavelength. The cellophane half-waveplate was used to convert an ordinary laptop screen, a camera phone, a laparoscope, a camcorder, and most recently a microscope into a three-dimensional display. Click illustrated explanation to learn more about this exciting new development. Iizuka's results were published recently in Review of Scientific Instruments and Applied Optics:

K. Iizuka, "Cellophane as a half-waveplate and its use for converting a laptop computer screen into a 3D display," Rev. Sci. Instrum. 74, 3636-3639 (2003).

K. Iizuka, "Three-dimensional camera phone," Appl. Opt. 43, 6285-6292 (2004).

K. Iizuka, “Three-dimensional microscope,” to be presented at BiOS 2008, SPIE Photonics West, San Jose, January 21, 2008.

Converting a plain ordinary laparoscope into a three-dimensional (3D) laparoscope by use of cellophane to manipulate the direction of light polarization

For an enlarged view, click the individual figures shown above.

A unique feature of this 3D laparoscope is that it includes a virtual ruler to measure axial distances without physically touching affected area. The cover page picture to the left shows (a) Light traces showing the superimposed image of the light ruler. (b)Without the light ruler, (c) With the light ruler touching the gallbladder, and (d) With the light ruler penetrating into the gallbladder.

The structure is sturdy and displays true color in real time and its diameter is no bigger than a standard 10 mm diameter laparoscope.:

K. Iizuka, "3D laparoscope based on the manipulation of polarized light by a cellophone half waveplate," Appl. Opt. 44, 7083-7090 (2005).

A simple method for verifying the birefringence of the cellophane sheet for 3D displays

Click the image for a larger view.

There are many kinds of clear wrapping paper on the market. Some look just like cellophane, but they are not birefringent (no fast and slow axes). This article includes an explanation of a simple polariscope improvised by two polarizer sheets for verifying the birefringence necessary for the 3D display application.

K. Iizuka, "Three-dimensional camcorder," Optical Engineering 46, 103203 (2007).

Physics News Update is a digest of physics news items arising from physics meetings, physics journals, newspapers and magazines, and other news sources. Iizuka's article in Review of Scientific Instruments, August 2003, was featured in Physics News Update:

Schewe, P., Riordon, J., Stein, B. (2003, August 13). Cellophane and 3D Displays.
Physics News Update, 649(3). Retrieved from: http://www.aip.org/enews/physnews/2003/split/649-3.html

Optics.org is an online photonics resource designed to serve the information needs of the worldwide photonics community. Click the link below to read Jacqueline Hewett's news article on Iizuka's discovery:

Hewett, J. (2003, August 5). Cellophane wraps up 3D displays. Optics.org, IOP Publishing Limited. Retrieved from: (2003, August 13). http://optics.org/articles/news/9/8/5/1

Hewett, J. (2004, December 10). Cellophane creates 3D camera phone. Optics.org, IOP Publishing Limited. Retrieved from: (2004, December 13). http://optics.org/articles/news/10/12/10/1

Divergence Ratio Axi-Vision Camera (Divcam) for practical applications

Fig. 6(a) Fingerprint remotely
taken without contact to the
finger by the Divcam. (b) Depth map of the fingerprint along the red cursor in (a).

The decay rate of the illuminating light with distance due to the divergence of the light is used as a means of mapping the distance. Click here for the principle of operation. Special features of this camera are its high resolution, real time operation, simplicity, compactness, light weight, portability, and yet low fabrication cost.

K. Iizuka, "Divergence Ratio Axi-Vision Camera (Divcam)," Rev. Sci. Instrum. 77, 045111 (2006).

Axi-Vision Camera for a virtual studio

The Axi-Vision Camera is a 3D television camera that can capture depth images simultaneously with the color image. Since the invention, this technique has been employed as a standard image-synthesizing technique that combines camera-based images with computer-generated graphics, and a new technical word "depth-keying synthesis" was born. Programs produced by this synthesis have been broadcast from NHK, Japan.

M. Kawakita, K. Iizuka, T. Aida, H. Kikuchi, H. Fujikake, J. Yonai and K. Takizawa, "Axi-Vision Camera (real-time distance-mapping camera)," Appl. Opt. 39, 3931-3939 (2000).

M. Kawakita, K. Iizuka, T. Aida, T. Kurita, and H. Kikuchi ,“Real-time three-dimensional video image composition by depth information,” IEICE Electronics Express 1, 237-242 (2004).

M. Kawakita, K. Iizuka, H. Nakamura, I Mizuno, T. Kurita, T. Aida, Y. Yamanouchi, H. Mitsumine, T. Fukaya, H. Kikuchi, and F. Sato, “High-definition real-time depth-mapping TV camera: HDTV Axi-Vision Camera," Optics Express 12, 2781-2794 (2004).

M. Kawakita, K. Iizuka, R. Iwama, K. Takizawa, H. Kikuchi,”Gain modulated Axi-Vision Camera (high speed high-accuracy depth-mapping camera)," Optics Express 12, 5336-5344 (2004).

Optics in 2002

In a contest sponsored annually by Optics and Photonics News of the Optical Society of America, the paper on the Axi-Vision Camera was selected as one of the most significant scientific accomplishments described in a refereed journal in 2002.

[Fujio Frontier Award]

The Institute of Image Information and Television Engineers of Japan presented the NHK team members and the Iizuka team members the 2003 Fujio Frontier Award in recognition of their leading edge research and development of the Axi-Vision Camera.

To view scenes recorded with the aid of the Axi-Vision Camera, click the following links:

Depth-keying is demonstrated with a beverage can
Woman is hidden or visible depending on distance
Revolving planets show 3D effect

Three-dimensional laser microvision

ATR Award

The combination of the invention of the ultra high precision phase discriminator with a superstructure grating laser source made possible an optical version of the microwave synthetic aperture radar. Three-dimensional laser microvision, being radar in nature, alleviates the common shortcoming of the uncomfortably shallow depth of focus of a high power microscope. Advanced Telecommunication Research presented Iizuka's team the ATR Excellence in Research Award for this project in 1996.

H. Shimotahira, K. Iizuka, S-C Chu, C. Wah, F. Costen and Y. Yoshikuni, "Three-dimensional laser microvision," Appl. Opt. 40, 1784-1794 (2001).

S. Fujii and K. Iizuka, "Neural network step-frequency fault locator," Opt. Eng. 34, 1441-1449 (1995).

H. Shimotahira, K. Iizuka, F. Taga and S. Fujii, "3D laser microvision," Opt. Methods in Biomedical and Environmental Sci., editors H. Ohzu and S. Komatsu (Elsevier, New York, 1994) pp.113-116.

K. Iizuka and S. Fujii, "Neural-network laser radar," Appl. Opt. 33, 2492- 2501 (1994).

S. Fujii and K. Iizuka, "Step frequency laser radar for locating faults in integrated optics substrates," (in Japanese) Jpn. J. Appl. Phys. 61, 939-942 (1992).

Y. Imai, M. Imai and K. Iizuka, "OFDR diagnostics by phase change detection," Trans. Inst. Electron. Commun. Eng. Jpn. E-75-B, 281-284 (1992).

K. Iizuka, Y. Imai, A. Freundorfer, R. James, R. Wong and S. Fujii, "Optical step frequency reflectometer," J. Appl. Phys. 68, 932-936 (1990).

K. Iizuka, A. P. Freundorfer, K. H. Wu, H. Mori, H. Ogura, V-K. Nguyen, "Step-frequency radar" J. Appl. Phys. 56, 2572-2583 (1984).

K. Iizuka, "Acoustic time-domain reflectometer used as a short-range fiber optic fault locator," Proc. IEEE 70, 683-684 (1982).