초록 ▼

An optical recording medium is arranged such that respective information recorded on lands and grooves are reproducible by either of a light beam of a first wavelength λ1 and a light beam of a second wavelength λ2 which is shorter than the first wavelength λ1. The groove depth d of the optical recor

An optical recording medium is arranged such that respective information recorded on lands and grooves are reproducible by either of a light beam of a first wavelength λ1 and a light beam of a second wavelength λ2 which is shorter than the first wavelength λ1. The groove depth d of the optical recording medium is such that tracking error signals of not less than a predetermined level can be ensured for respective wavelengths λ1 and λ2 without generating distortion in waveform, irrespectively of differences in receiving light sensitivity of a photodetector provided in a optical pickup devices for use in recording and reproducing information on and from such optical recording medium.

대표청구항 ▼

1. An optical recording medium, comprising:lands and grooves, said optical recording medium at least being reproducible by either of i) a light beam having a first wavelength λ1 set in a range of not less than 630 nm to not more than 680 nm, and ii) a light beam having a second wavelength λ2 set in

1. An optical recording medium, comprising:lands and grooves, said optical recording medium at least being reproducible by either of i) a light beam having a first wavelength λ1 set in a range of not less than 630 nm to not more than 680 nm, and ii) a light beam having a second wavelength λ2 set in a range of not less than 390 nm to not more than 430 nm, wherein said groove depth d satisfies the conditions of: λ1/n1×(3/64)?d?λ1/n1×(13/64); and λ2/n2×(4/64)?d?λ2/n2×(12/64), wherein n1 and n2 indicate refractive indexes of said optical recording medium for the first wavelength λ1 and the second wavelength λ2 respectively. 2. The optical recording medium as set forth in claim 1, wherein:the first wavelength λ1 is set within a range of from 630 nm to 680 nm. 3. The optical recording medium as set forth in claim 1, wherein:the second wavelength λ2 is set within a range of from 390 nm to 430 nm. 4. The optical recording medium as set forth in claim 1, wherein:said groove depth d satisfies the conditions of: λ1/n1×(3/64)?d?λ1/n1×(13/64); and λ2/n2×(6/64)?d?λ2/n2×(10/64). 5. The optical recording medium as set forth in claim 1, wherein:information can be recorded on both said lands and grooves. 6. The optical recording medium as set forth in claim 1, wherein:said lands and grooves are formed in virtually same width. 7. The optical recording medium as set forth in claim 6, wherein:an interval between centers of adjacent grooves is not less than 1.95 times of a beam spot diameter of the light beam having the second wavelength λ2. 8. The optical recording medium as set forth in claim 1 being a super-resolution magnetic medium.9. An optical pickup device for recording and reproducing information with respect to the optical recording medium of claim 1, comprising:a light source for emitting the light beam having the second wavelength λ2, and a photodetector for receiving light reflected from said optical recording medium, wherein said photodetector has a receiving light sensitivity s2 with respect to the second wavelength λ2 satisfying the condition of: s2/s1?0.73, wherein s1 is a receiving light sensitivity of said photodetector with respect to the first wavelength λ1. 10. An optical pickup device for recording and reproducing information with respect to the optical recording medium of claim 4, comprising:a light source for emitting the light beam having the second wavelength λ2, and a photodetector for receiving light reflected from said optical recording medium, wherein said photodetector has a receiving light sensitivity s2 with respect to the second wavelength λ2 satisfying the condition of: s2/s1?0.57, wherein s1 is a receiving light sensitivity of said photodetector with respect to the first wavelength λ1. 11. An optical recording medium, comprising:lands and grooves, said optical recording medium at least being reproducible by either of i) a light beam having a first wavelength λ1 set in a range of not less than 630 nm to not more than 680 nm, and ii) a light beam having a second wavelength λ2 set in a range of not less than 390 nm to not more than 430 nm, wherein said grooves are formed in width within a range of from 0.5 μum to 0.6 μum, and in depth d within a range of from 19.4 nm to 47.5 nm. 12. The optical recording medium as set forth in claim 11, wherein:said grooves are formed in depth d within a range of from 19.4 nm to 45 nm. 13. The optical recording medium as set forth in claim 11, wherein:said grooves are formed in depth d within a range of from 23.7 nm to 39.5 nm. 14. The optical recording medium as set forth in claim 11, wherein:the first wavelength λ1 is set within a range of from 630 nm to 680 nm. 15. The optical recording medium as set forth in claim 11, wherein:the second wavelength λ2 is set within a range of from 390 nm to 430 nm. 16. The optical recording medium as set forth in claim 11, wherein:information can be recorded on both said lands and grooves. 17. The optical recording medium as set forth in claim 11, wherein:said lands and grooves are formed in virtually same width. 18. The optical recording medium as set forth in claim 17, wherein:an interval between centers of adjacent grooves is not less than 1.95 times of a beam spot diameter of the light beam having the second wavelength λ2. 19. The optical recording medium as set forth in claim 11 being a super-resolution magnetic medium.20. An optical pickup device for recording and reproducing information with respect to the optical recording medium of claim 11, comprising:a light source for emitting the light beam having the second wavelength λ2, and a photodetector for receiving light reflected from said optical recording medium, wherein said photodetector has a receiving light sensitivity s2 with respect to the second wavelength λ2 satisfying the condition of: s2/s1?0.73, wherein s1 is a receiving light sensitivity of said photodetector with respect to the first wavelength λ1. 21. An optical pickup device for recording and reproducing information with respect to the optical recording medium of claim 13, comprising:a light source for emitting the light beam having the second wavelength λ2, and a photodetector for receiving light reflected from said optical recording medium, wherein said photodetector has a receiving light sensitivity s2 with respect to the second wavelength λ2 satisfying the condition of: s2/s1?0.57, wherein s1 is a receiving light sensitivity of said photodetector with respect to the first wavelength λ1. 22. An optical recording medium, comprising:lands and grooves, said optical recording medium at least being reproducible by either of i) a light beam having a first wavelength λ1 set in a range of not less than 630 nm to not more than 680 nm, and ii) a light beam having a second wavelength λ2 set in a range of not less than 390 nm to not more than 430 nm, wherein said groove depth d satisfies the condition of: λ1/n1×(3/64)?d?λ1/n1×(13/64), wherein n1 indicates a refractive index of said optical recording medium for the first wavelength λ1, and a reflective index r1 of said optical recording medium with respect to the first wavelength λ1 is smaller than a reflective index r2 with respect to the second wavelength λ2. 23. The optical recording medium as set forth in claim 22, wherein:the first wavelength λ1 is set within a range of from 630 nm to 680 nm. 24. The optical recording medium as set forth in claim 22, wherein:the second wavelength λ2 is set within a range of from 390 nm to 430 nm. 25. The optical recording medium as set forth in claim 22, wherein:information can be recorded on both said lands and groove. 26. The optical recording medium as set forth in claim 22, wherein:said lands and grooves are formed in virtually same width. 27. The optical recording medium as set forth in claim 26, wherein:an interval between centers of adjacent grooves is not less than 1.95 times of a beam spot diameter of the light beam having the second wavelength λ2. 28. The optical recording medium as set forth in claim 22 being a super-resolution magnetic medium.