1. |
|
|
2. |
- Carlsson, Torgny E., et al.
(författare)
-
Development of a 3D camera
- 1999
-
Ingår i: Proceedings of SPIE. ; , s. 218-224
-
Konferensbidrag (refereegranskat)abstract
- In the development of new products there are two parallel lines for the development process to follow; the traditional or 'real,' and the new computer aided or 'virtual.' The traditional line is to develop prototypes that can be used for testing strength, functionality, and visual appearance of the product. In the virtual line digital (CAD) models are developed which can be tested entirely in a computer by simulations e.g., using Finite Element Analysis (FEA) and other tools. For transformation from the real to the virtual world some kind of 3D camera is needed. The shape of the model should be measured together with further data concerning the visual appearance, material properties, etc. We have developed electronic recording techniques for doing this based on the Light-in-Flight technique. This technology has all advantages of holography, i.e., apart from the shape it is also possible to measure how much light is reflected from different parts of the object along with interferometric information, which can give mechanical data for the object. This can be used for example for visualization and to give tactile and haptic information to a virtual reality system about how the object would be perceived by a person touching it.
|
|
3. |
- Carlsson, Torgny E., et al.
(författare)
-
Method for fringe enhancement in holographic interferometry for measurement of in-plane displacements
- 1998
-
Ingår i: Applied Optics. - : Optical Society of America. - 0003-6935 .- 1539-4522. ; 37:10, s. 1845-1848
-
Tidskriftsartikel (refereegranskat)abstract
- Theoretical background along with experimental results are given for a simple method for in-plane fringe enhancement in dual-beam illumination holographic interferometry. In this method, the fringes representing in-plane displacements arise as a moirépattern between two interferograms. To distinguish the in-plane displacement, a sequence of images is recorded while the reference mirror is continuously tilted at random. The in-plane fringes arethen found as the maximum contrast of the out-of-plane fringes in the image sequence. The resulting fringe quality is close to the quality of the out-of-plane fringes.
|
|
4. |
- Carlsson, Torgny E., et al.
(författare)
-
System for acquisition of three-dimensional shape and movement using digital Light-in-Flight holography
- 2001
-
Ingår i: Optical Engineering. - : SPIE-Intl Soc Optical Eng. - 0091-3286 .- 1560-2303. ; 40:1, s. 67-75
-
Tidskriftsartikel (refereegranskat)abstract
- In the development of new products there are two parallel lines for the development process to follow: the traditional or "real" and the new computer aided or "virtual." The traditional line is to develop prototypes that can be used for testing strength, functionality, and visual appearance of the product. In the virtual line digital (CAD) models are developed that can be tested entirely in a computer by simulations, e.g., using finite element analysis (FEA) and other tools. For transformation from the real to the virtual world some kind of 3-D acquisition system is needed. The shape of the model should be measured together with further data concerning the visual appearance, material properties, etc. We develop electronic recording techniques for doing this based on the Light-in-Flight technique. This technology has all the advantages of holography, i.e., apart from the shape it is also possible to measure how much light is reflected from different parts of the object along with interferometric information, which can give mechanical data for the object. This can be used, for example, for visualization and to give tactile and haptic information to a virtual reality system about how the object would be perceived by a person touching it.
|
|
5. |
- Carlsson, Torgny, et al.
(författare)
-
Practical system for time-resolved holographic interferometry
- 1991
-
Ingår i: Optical Engineering. - : SPIE-Intl Soc Optical Eng. - 0091-3286 .- 1560-2303. ; 30:7, s. 1017-1022
-
Tidskriftsartikel (refereegranskat)abstract
- An easily implemented and easily manageable system for time-resolved holographic interferometry is presented. The system consists of a multiple-pulsed Q-switched ruby laser and a rotating disk having radial slits with a constant angular separation. The disk is used to scan the reference beam along a holographic plate, thereby achieving spatial multiplexing. Since the influence on the beam is negligible and a single slit is illuminated by every laser pulse, there is no need for synchronization. The interferometric pattern is achieved by removing the disk and exposing a reference image on the holographic plate. The system may serve as an excellent tool for full-field dynamic measurements. A simple experiment has beem performed showing a sequence of momentary interference patterns on a vibrating plate.
|
|
6. |
- Gustafsson, E. Martin I., et al.
(författare)
-
Relative ultrasound energy measurement circuit
- 2005
-
Ingår i: 2005 IEEE International Workshop on Intelligent Signal Processing. - Piscataway, NJ : IEEE Communications Society. - 078039030X - 0780390318 ; , s. 322-327
-
Konferensbidrag (refereegranskat)abstract
- A relative ultrasound energy estimation circuit has been designed in a standard 0.35-μm CMOS process, to be a part of a thumb size internet connected wireless ultrasound measurement system. This circuit measures the relative energy between received ultrasound pulses, and presents an output signal that is linear to the received energy. Post-layout simulations indicate 7 bit linearity for 500 mV input signals, 5 μsec startup and stop times, 2.6 mW power consumption during active state. The active area measures 0.6 mm2 including digital logic, bias generation, and an on-chip oscillator. The circuit has been sent for manufacturing in the austrianmicrosystems C35B4 process via Europractice MPW.
|
|
7. |
- Gustafsson, Jonny, et al.
(författare)
-
Development of a 3D interaction table
- 2004
-
Ingår i: STEREOSCOPIC DISPLAYS AND VIRTUAL REALITY SYSTEMS XI. - BELLINGHAM : SPIE-INT SOC OPTICAL ENGINEERING. - 0819451940 ; , s. 509-516
-
Konferensbidrag (refereegranskat)abstract
- We have identified the need for, and started development of, a new tool we call an interaction table. In this paper the experiences with the first prototype are described. The interaction table presents a computer-generated, autostereoscopic, three-dimensional image that can be viewed and interacted with.
|
|
8. |
- Gustafsson, Jonny
(författare)
-
Finding new wavelengths for pulsed holography
- 2000
-
Ingår i: Proceedings of SPIE. ; , s. 353-358
-
Konferensbidrag (refereegranskat)abstract
- A short popular overview is given of the possibilities of finding new pulsed laser sources for making holograms. Special emphasis is made on wavelengths suitable for color holography.
|
|
9. |
- Gustafsson, Jonny
(författare)
-
Holography in Sweden 2000
- 2000
-
Ingår i: Proceedings of SPIE. ; , s. 52-53
-
Konferensbidrag (refereegranskat)abstract
- Looking back on the earlier reports on Holography in Sweden, it is striking that not much has changed during the last decade. It is more or less the same people that have been active throughout this period. It is difficult to say if holography is loosing or winning ground in Sweden. In spite of this a lot of new and interesting work has been done.
|
|
10. |
- Gustafsson, Jonny
(författare)
-
Holoviewer system for preproduction of holographic stereograms
- 1999
-
Ingår i: Proceedings of SPIE. ; , s. 84-92
-
Konferensbidrag (refereegranskat)abstract
- A system for transmission and previsualization of digital data for production of holographic stereograms has been developed. The aim of this system is to help the communication between producers of holographic stereograms and their clients. The client accesses the system through a Java applet, a small program, which is automatically downloaded and run on the clients local computer. The client loads a file in VRML format into the applet and the 3D model is displayed using the VRML browser plug-in usually delivered with WWW browsers. The Java applet overrides the controls of the VRML browser and provides only the manipulations possible and necessary for preparing the hologram production and visualizing the result. The applet permits the client to somewhat modify the scene e.g. by adding lights and manipulating them. After finishing the settings and visualizations of the hologram, the client may save the file with the new settings on her own computer in order to resume work later on. When satisfied she may upload the file with all settings to the hologram producer. The computer of the hologram producer is running a small, specially designed http server which will receive the file from the client for further handling.
|
|