Aperture type fluorescent lamp

• US 5,903,095 A
• Filed: 09/12/1997
• Issued: 05/11/1999
• Est. Priority Date: 03/07/1997
• Status: Expired due to Fees

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Abe, Tomonori, Terada, Toshiyuki, Yoshida, Mitsunari, Kawasaki, Kazuaki
• Primary Examiner(s): Patel, Ashok
• Application Number:
  US08/928,835
• Time in Patent Office: 606 Days
• Field of Search: 313/493, 313/572, 313/573, 313/607, 313/594, 313/234, 313/635, 313/485
• US Class Current: 313/485
• CPC Class Codes: H01J 61/35 provided with coatings on the walls thereof; Selection of materials for the coatings using coloured coatings H01J61/40; using luminescent coatings H01J61/42
• CPC Class Codes: H01J 61/42 by transforming the wavelength of the light by luminescence
• CPC Class Codes: H01J 61/70 Lamps with low-pressure unconstricted discharge having a cold pressure < 400 Torr
• CPC Class Codes: H01J 65/046 the field being produced by using capacitive means around the vessel

Abstract

There is provided an aperture type fluorescent lamp comprising a tubular bulb, an electrode, and a fluorescent layer formed on an inner surface of said tubular bulb in an axial direction of the tubular bulb, an aperture portion provided in said fluorescent layer along the axial direction of the tubular bulb so as to be made the aperture portion as a radiation portion, wherein said aperture portion comprises an aperture portion fluorescent layer having a thickness smaller than the fluorescent layer of other portions. The fluorescent lamp according to the present invention makes it possible to eliminate nonuniformitiy in illuminance.

Claims

1. An aperture type fluorescent lamp comprising a tubular bulb, an electrode, and a fluorescent layer formed on an inner surface of said tubular bulb in an axial direction of the tubular bulb, an aperture portion provided in said fluorescent layer along the axial direction of the tubular bulb so as to be made the aperture portion as a radiation portion, wherein said aperture portion comprises an aperture portion fluorescent layer having a thickness smaller than the fluorescent layer of other portions.

2. The aperture type fluorescent lamp according to claim 1, wherein said electrode comprises a thermo-electrode provided at both ends of said tubular bulb.

3. The aperture type fluorescent lamp according to claim 1, wherein said electrode comprises a cold cathode provided at both ends of said tubular bulb.

4. The aperture type fluorescent lamp according to claim 1, wherein said electrode comprises a pair of external electrodes provided on an outer surface of said tubular bulb and facing each other.

5. The aperture type fluorescent lamp according to claim 1, wherein said electrode comprises an internal electrode provided at the center in the axial direction of the tubular bulb and an external electrode provided on an outer surface of said tubular bulb.