Title:
RAY CUT FILTER
Document Type and Number:
Japanese Patent JP3937823
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a ray cut filter which can obtain transmission factor characteristics close to human eyes, in a region ranging from ultraviolet region to visible region, and which can also properly cut the ray in the ultraviolet band.
SOLUTION: The ray cut filter is constituted so that it can cut the ray of the ultraviolet region, and that it may hold a transmission factor characteristics, in which the transmission factor gently rises according as the wavelength becomes longer in the low wavelength side of the visible region. To be specific about the transmission factor characteristics, in the range where the wavelength is 400 nm to 500 nm, the transmission factor rises gently from the prescribed value within the range of 1% to 5% to the prescribed value within the range of 90% to 98%, according as the wavelength becomes longer.
Inventors:
Kameda Eiichi
Application Number:
JP2001364483A
Publication Date:
June 27, 2007
Filing Date:
November 29, 2001
Export Citation:
Assignee:
Great Vacuum Co., Ltd.
International Classes:
G02B5/28; G02B5/22; (IPC1-7): G02B5/28; G02B5/22
Domestic Patent References:
| JP10170822A | ||||
| JP63259501A | ||||
| JP11202126A | ||||
| JP2000209510A | ||||
| JP2001272633A |
Attorney, Agent or Firm:
Yoshiro Kurauchi