← Back to Patent Explorer
US4086605A Expired / Lapsed US ⏱️ 0.0 years remaining

Diaphragm device

Assignee: Canon Inc
•
Filing: 1976-06-16
•
Granted: 1978-04-25
•
Expires: 1996-06-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In a diaphragm device for use in an optical instrument such as a camera and having two or more diaphragm blades movable across an imaging path of rays and arranged in axially displaced relation from each other to define a common aperture of variable size, there is provided means formed in a portion of at least one of the diaphragm blades to substantially either eliminate or reduce the axial displacement between the diaphragm blades at a relatively small aperture region, whereby the distribution of light energy is made uniform over the entire area of the image.

Inventors

  • 👤 Kazuo Ishikawa
  • 👤 Keiichi Sakaguchi
  • 👤 Tomoshi Takigawa
  • 👤 Noritsugu Hirata
  • 👤 Akira Tajima
  • 👤 Sadahiko Tsuji

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 13:33
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/02; G03B9/06

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 168 words
A diaphragm device to regulate the amount of light passing therethrough, comprising: at least two light intercepting blades which respectively have openings to allow light to pass therethrough and define one diaphragm aperture to regulate an amount of light passing therethrough by having each of said openings mutually cooperate, said blades being arranged in an overlapping relationship to each other with a certain space therebetween to avoid contact with each other and operating to vary a diaphragm aperture to regulate the amount of light passing therethrough by being relatively shifted while maintaining said space therebetween, at least one of said blades having an opening part formed in a manner protruding to a side facing to the other of said blades for defining said diaphragm aperture with a small diameter at a position closer to the other of said blades, said opening part being formed in correspondence to a particular portion of the opening of said at least one blade to define a diaphragm aperture with a small diameter.
Claim 2
Dependent Claim 168 words
A diaphragm device to regulate the amount of light passing therethrough, comprising: at least two light intercepting blades which respectively have openings to allow light to pass therethrough and define one diaphragm aperture to regulate an amount of light passing therethrough by having each of said openings mutually cooperate, said blades being arranged in an overlapping relationship to each other with a certain space therebetween to avoid contact with each other and operating to vary a diaphragm aperture to regulate the amount of light passing therethrough by being relatively shifted while maintaining said space therebetween, at least one of said blades having an opening part formed in a manner protruding to a side facing to the other of said blades for defining said diaphragm aperture with a small diameter at a position closer to the other of said blades, said opening part being formed in correspondence to a particular portion of the opening of said at least one blade to define a diaphragm aperture with a small diameter.
Claim 3
Dependent Claim 37 words
A diaphragm device according to claim 1, wherein said opening part is formed at said at least one blade in a manner avoiding contact with said other blade when defining a diaphragm aperture with a small diameter.
Claim 4
Dependent Claim 37 words
A diaphragm device according to claim 1, wherein said opening part is formed at said at least one blade in a manner enabling contact with said other blade when defining a diaphragm aperture with a small diameter.
Claim 5
Dependent Claim 207 words
A diaphragm device to regulate the amount of light which reaches said device through an objective lens means having an optical axis and which passes therethrough, said device comprising: a first light intercepting blade having a first opening to allow light to pass therethrough, said first blade being provided within a first plane almost perpendicular the optical axis of said objective lens means, and a second light intercepting blade having a second opening to allow light to pass therethrough, said second blade being provided within a second plane almost parallel to said first plane and separated from said first plane by a very small space and in an overlapping relationship with the first plane, said second blade operating to define one diaphragm aperture to regulate the amount of light passing therethrough by having said second opening cooperate with said first opening at said first blade, said second blade further having an opening part formed in a manner protruding to a side facing to said first blade to define said diaphragm aperture with a small diameter at a position closer to said first blade, said opening part being formed corresponding to a part of said second opening applied particularly to define a diaphragm aperture with a small diameter.
Claim 6
Dependent Claim 207 words
A diaphragm device to regulate the amount of light which reaches said device through an objective lens means having an optical axis and which passes therethrough, said device comprising: a first light intercepting blade having a first opening to allow light to pass therethrough, said first blade being provided within a first plane almost perpendicular the optical axis of said objective lens means, and a second light intercepting blade having a second opening to allow light to pass therethrough, said second blade being provided within a second plane almost parallel to said first plane and separated from said first plane by a very small space and in an overlapping relationship with the first plane, said second blade operating to define one diaphragm aperture to regulate the amount of light passing therethrough by having said second opening cooperate with said first opening at said first blade, said second blade further having an opening part formed in a manner protruding to a side facing to said first blade to define said diaphragm aperture with a small diameter at a position closer to said first blade, said opening part being formed corresponding to a part of said second opening applied particularly to define a diaphragm aperture with a small diameter.
Claim 7
Dependent Claim 109 words
A diaphragm device according to claim 4, wherein said first light intercepting blade is further provided with an opening part formed in a manner protruding to a side facing to said second blade to define a diaphragm aperture with a small diameter at a position closer to said second light intercepting blade when defining said diaphragm aperture with a small diameter, said opening part of the first blade being formed corresponding to a part of said first opening applied particularly to define a diaphragm aperture with a small diameter and defining said diaphragm aperture with a small diameter by cooperating with said opening part provided at said second blade.
Claim 8
Dependent Claim 91 words
A diaphragm device according to claim 5, further comprising driving means electrically connected with exposure measuring circuit means and responsive to the output of the circuit means, said driving means having an output member, said first light intercepting blade being operatively connected with said output member of the driving means and driven by the output member so as to operate within said first plane, while said second light intercepting blade is operatively connected with said first blade and driven by said first blade so as to operate within said second plane.
Claim 9
Dependent Claim 45 words
A diaphragm device according to claim 5, wherein each of said opening parts at said first and second blades is formed respectively at the first and second blades in a manner avoiding contact with each other when defining a diaphragm aperture with a small diameter.
Claim 10
Dependent Claim 45 words
A diaphragm device according to claim 5, wherein each of the opening parts at said first and second blades is formed respectively at the first and second blades in a manner enabling contact with each other when defining a diaphragm aperture with a small diameter.
Claim 11
Dependent Claim 91 words
A diaphragm device according to claim 4, further comprising driving means electrically connected with exposure measuring circuit means and responsive to the output of the circuit means, said driving means having an output member, said first light intercepting blade being operatively connected with said output member of the driving means and driven by the output member so as to operate within said first plane, while said second light intercepting blade is operatively connected with said first blade and driven by the first blade so as to operate within said second plane.
Claim 12
Dependent Claim 91 words
A diaphragm device according to claim 4, further comprising driving means electrically connected with exposure measuring circuit means and responsive to the output of the circuit means, said driving means having an output member, said second light intercepting blade being operatively connected with said output member of the driving means and driven by the output member so as to operate within said second plane, while said first light intercepting blade is operatively connected with said second blade and driven by the second blade so as to operate within said first plane.
Claim 13
Dependent Claim 37 words
A diaphragm device according to claim 4, wherein said opening part at the second blade is formed at the second blade in a manner avoiding contact with said first blade when defining diaphragm aperture with small diameter.
Claim 14
Dependent Claim 39 words
A diaphragm device according to claim 4, wherein said opening part at the second blade is formed at the second blade in a manner enabling contact with said first blade when defining a diaphragm aperture with a small diameter.

References Cited (Backward Citations)

US993431A Cited
US3442194A Cited
US3633486A Cited
US3846807A Cited
US4009946A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-04-24 1981-10-24 1982-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-04-24 1985-10-24 1986-04-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-04-24 1989-10-24 1990-04-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag