Publication Number:	SI20775A
Application Date:	25. 8. 2000
Assignee/Applicant:	Jožef Stefan Institute [SI]
Inventor:	Marko Zgonik
Title:	Konfokalni holografski optični pomnilnik brez prekrivanja zapisov [SL], Cofocal Holographic Optical Memory Without Record Overlapping [EN]
Description:	The invention includes a method and system for storing data in the form of non-overlapping volumetric holograms. The storage media is a light sensitive material in the shape of a disk with thickness D, while the individual holograms inside it are approximately cylinder-shaped with the minimum possible diameter. The signal light beam is modulated by data and focused by a lens or appropriate optical system to the storage surface, where it illuminates a minimum surface of material compared to the quantity of data. For the recording of a hologram a reference light beam can be used, which can come to the storage surface from the same side as the signal beam or the opposite one. The invention differs from the currently known applications by the fact that the reference light beam is used for recording, which in the optimum case illuminates only the smallest possible volume of storage material. The hologram is recorded only in areas where the signal and the reference light beam overlap therefore its volume is equal to the volume, illuminated by the reference beam. Any following holograms containing data are recorded to adjacent parts of the surface, so that they do not overlap. The density of the light flux inside the panel is in the reference beam usually greater than in the signal, therefore the erasing of adjacent holograms is almost negligible. Even the reading of a hologram is non-destructive and kept to a minimum. The described invention provides the maximum possible theoretical record density.
Drawings:
Category:	Physical Sciences
Technology application codes:	Physical and exact sciences, Electronics, IT and telecoms
Market application codes:	Computer related, Industrial products
www:	https://worldwide.espacenet.com/patent/search/family/020432704/publication/SI20775A?q=si20775
Patent offices:	UIL RS

 

Extended patent application

---

Publication Number:	AU7883701A
Application Date:	22. 8. 2001
Assignee/Applicant:	Jožef Stefan Institute [SI]
Inventor:	Marko Zgonik
Title:	Confocal Holographic Optical Storage With Non-overlapping records
www:	https://worldwide.espacenet.com/patent/search/family/020432704/publication/AU7883701A?q=pn%3DAU7883701A

 

Extended patent application

---

Publication Number:	WO0221535A1
Application Date:	22. 8. 2001
Assignee/Applicant:	Jožef Stefan Institute [SI], Zgonik Marko [SI]
Inventor:	Marko Zgonik
Title:	Confocal Holographic Optical Storage With Non-overlapping records
www:	https://worldwide.espacenet.com/patent/search/family/020432704/publication/WO0221535A1?q=pn%3DWO0221535A1

 

Extended patent application

---

Publication Number:	US6781725B2
Application Date:	19. 2. 2003
Assignee/Applicant:	Jožef Stefan Institute [SI]
Inventor:	Marko Zgonik
Title:	Confocal Holographic Optical Storage With Non-overlapping records
www:	https://worldwide.espacenet.com/patent/search/family/020432704/publication/US6781725B2?q=US6781725B2