1. No category

350*464
OR
‘218289611
v ‘April 1, 1958
SEARCH ROOM
7.
sABuRo MURAKAMI
2,828,671
WIDE APERTURE PHOTOGRAPHIC OBJECTIVES
73253?
Filed Jan. 3, 1957
uvmvrox.
,BY SABUK Mum/mm
1%
,7’ Amway
}
2,828,671
United States Patent-- 0 M CC
-
Patented Apr. 1, 1958
1
2
'
v
and curvature of ?eld, for a ?eld angle of 46° can be
obtained.
2,828,671
Example
WIDE APERTURE PHOTOGRAPHIC OBJECTIVES
Saburo Murakami, Kawasaki City, Japan, assignor to
The illustrative embodiment according to this inven
tion’illustrated in the sole ?gure of the attached drawing
has the following detailed characteristics:
Nippon Kogaku K. K., Tokyo, Japan, a corporation
of Japan
[f=100
Application January 3, 1957, Serial No. 632,339
Claims priority, application Japan April 10, 1956
F:1.1
'
Axial
Focal Length
0t‘ Component
Radius
.
graphic objectives.
.
fr] =+338. 9
'
d3 = 8. 5
n2=1. 6073
v1=59.5
vz=59. 5
d4 = 1.4
20
n =+ 53. 5
_
Jui=—823.7
bodiment of the objective according to this invention of
which the third and the fourth components each consists
d5 =19. 4
m=1. 7170
v3=47. 9
do = 4.1
m=1.5927
v4=35.4
n =+872. 1
r1 =+ 33.3
(11 =25. 2
T3 =— 42. 6
of a pair of cemented lenses.
In the photographic objective according to this inven 25
tion, the ?rst component I, that is, the ?rst lens element,
and the second component II, that is, the second lens
j1v =+2309. 5
element, are each a positive meniscus lens with its convex
fv =
surface towards the object. The third component III is a
cemented meniscus lens consisting of the third lens ele 30
ment, 2. single convex lens and the fourth lens element,
cemented third component facing towards the object. The
m=1. 6078
n =+163.8
The ?gure of the attached drawing illustrates an em
a single concave lens, the convex outer surface of the
d1= 8.7
dz = 0.6
r2 =+42S. 3
r3 =+ 93. 0
It is an object of the instant invention to provide a,
wide aperture photographic objective of superb photo
graphic power, comprising six components consisting of
.
’
Refractive
Abbe
Index
Number
r1 =+167.6
fr =+447.7
‘
nine lens elements.
Thickness
and
Separation
3 Claims. (CI. 88-57)
The instant invention relates to wide aperture photo 15
46°]
d; = 5.4
n5=1. 6483
vi=33.8
d9 =20. 5
m=1. 7170
vs=47.9
ft =+135. 7
rm=—- 58.1
dio= 0.6
162.2
m=+116.3
dn=11.0
nr-y-l. 7170
v1=47.9
{12: no
di2= O. 6
.
m=+142. 3
fv1= 300. 2
dl3= 2. 9
ns=1. 6259
vs=35.6
du= 7. 8
m=1. 6385
l7a=55. 5
Tu=+ 96. 9
'
m=+5l8.0
fourth component IV is a cemented meniscus lens con
sisting of the ?fth lens element, a single concave lens, 35 where rsubscrlpta nsubscrlpt and vsubscrlpt are as above Stated:
dsubsmpt is the thickness of the successive lenses and the
and the sixth lens element, a single convex lens, the convex
outer surface of the cemented fourth component facing I distance of the successive spacings at the optical axis, the
subscripts likewise increasing from the object to the image
towards the image plane. The ?fth component V, that
side of the objective, and a surface which is convex to
is, the seventh lens element, is a single convex lens. The
sixth component VI is a cemented positive meniscus lens 40 the incident light has a positive radius of curvature and
a concave surface has a negative radius of curvature.
comprising the eighth lens element, a single concave
It will be noted that the lenses of each the third and
lens, and the ninth lens element, a single convex lens, the
convex outer surface of the sixth component facing to
fourth components of the objective of my invention may
be slightly separated from each other rather than be inter
wards the object.
45 cemented as shown in the ?gure.
The respective absolute value of the focal length of
each component is designed to be not less than 1.1 f and
to minimize the individual portions of various aberra
tions, in which f denotes the resulting focal length of the
objective composed of the above lenses.
Stated more
particularly, by making
What I claim is:
j 1._ A wide aperture photographic objective comprising I
six aligned and spaced components consisting of a total
of nine lens elements, of which the ?rst component is a
?rst positive meniscus lens with its convex surface to
wards the object side of the objective, the second com
ponent is a second positive meniscus lens with its con
vex surface to the object side, the third component is a
cemented meniscus component consisting of a ?rst con
and observing the relation of n3>n4, mainly coma and 55
vex lens and a ?rst concave lens, the convex outer sur
astigmatic aberration can be minimized, .where rsubsmpt
face of the third component facin'g towards the object_
is the radius of curvature of the successive refractive
side, the fourth component is a cemented meniscus com
surfaces of the objective, nsubsmp, the refractive index
ponent consisting of a second concave lens and a second
on the d-line of the glass of the successive lenses, and
convex lens, the convex outer surface of the fourth com
vsubsmp, the Abbe number, representative of the disper 60 ponent
facing towards the image side of the objective, the
sive power, of the glass of successive lenses, the subscripts
?fth component is a single positive lens, the sixth com
increasing from the object to the image side of the objec
ponent is a cemented positive meniscus component con
tive. Furthermore by makingi '
sisting of a third concave lens and a thirdconvex lens,
the convex outer surface of the sixth component facing
65 the object side, each component has a focal length of an
absolute value not less than one-tenth in excess of the
and by observing the relation of n6>n5, coma can be min
imized.
total focal length of the objective, the index of refraction
By choosing 0.20 f<d7<0.35 f, curvature of
of the ?rst convex lens is greater than 1.69 and greater
than the index of refraction of the ?rst concave lens,
By the above mentioned design, superb photographic 70 the Abbe number of the ?rst convex lens lies between
objectives of F :1.1 with the minima of chromatic aberra- ’ 40 and 55, the outer convex surface of the third com
?eld can be minimized.
.
tion, spherical aberration, coma, astigmatic aberration
ponent has a radius of curvature of from 0.45 f to 0.60 f,
2,828,671
3
the outer concave surface of the third component has a
outer concave surface of the fourth component is of an
radius of curvature of from 0.25 f to 0.40 f, the index
of refraction of fhe second convex- lens is greater than
1.70 and greater than that of the second concave lens,
number of the ?rst convex lens lies between 40 and 55,
the Abbe number of the second convex lens lies between
the radius of curvature of the outer concave surface of
the fourth component has an absolute value lying be
tween 0.35 f and 0.50 f, the outer convex surface of the
absolute value lying between 0.35 f and 0.50 f, the Abbef
37 and 55, and the axial distance from the outer con
cave surface of the third component to the outer concave
fourth component has a radius of curvature of an ab
surface of the fourth component lies between 0.20 f and
0.35 f, where f is the total focal length of the objective.
solute value lying between 0.50 f and 0.65 f, the Abbe
3. A wide aperture photographic objective having the
number of the second convex lens lies between 37 and 10 following numerical data:
55, and the axial distance from the outer concave surface
[Focal length j= 100
F : 1.1
Field angle 46°]
of the third component to the outer concave surface of
the fourth component lies between 0.20 f and 0.35 f, where I
Axial
fis the total focal length of the objective.
2. A wide aperture photographic objective comprising 15
six aligned and spaced components consisting of a total
of nine lens elements of which the ?rst component is a
positive meniscus lens of which the convex surfaces faces
the object side of the objective, the second component
is a second positive meniscus lens of which the convex 20
surface faces the object side, the third component is a
meniscus array consisting of a ?rst convex lens closely
spaced from a ?rst concave lens in the direction to the
image side of the objective, the convex outer surface of
Focal Length
of Component
n =+167. 6
.
0.45 f and 0.60 f, the outer convex surface of the fourth
of the third component has a radius of curvature lying
between 0.25 f and 0.40 f, the radius of curvature of the
m=1.6073
v1==59. 5
d5 =19.4
m=1. 7170
0s=47.9
ds= 4. 1
m=l. 5927
v4=35. 4
d: = 8. 5
n =+163. 8
d4 = 1.4
rs =+ 53.5
’
fm=—823. 7
rs =+872. 1
r1 =+ 83.3 ,
.
.
d1 =25. 2
is =— 42. 6
flv= 2309.5
d3 = 5.4
n5=l.6483
05=33.8
dn =20. 5
m=1. 7170
0e==47. 9
du=11.0
n1=1. 7170
01:17.9
di2= 0.6
'
d1s= 2.9
m=1. 6259
va=35.6
d14= 7.8
m=1.6385
vn=55.5
fa =+135. 7
'
rm=— 58.1
,
d1o= 0.6
m=+116. 3
fv = 162.2
m
cave lens and a third convex lens, the convex outer sur~
component has a radius of curvature of absolute value 45
lying between 0.50 f and 0.65 f, the outer concave surface
m=59.5
I’: =+ 93.0
ft! =+33$.9
the convex outer surface of the-fourth component fac
objective, the index of refraction of the ?rst convex
lens is greater than 1.69 and greater than of the ?rst
concave lens, the index of refraction of the second convex
lens is greater than 1.70 and greater than that of the
second concave lens, the outer convex surface of the
third component has a radius of curvature lying between
m=1.6073
d1 = 0. 6
second concave lens closely spaced from a second convex '
face of the sixth component facing the object side, each
component has an individual focal length which is at 35
least one-tenth greater than the total focal length of the
.
d1 =87
I’: =+428. 3
the third component facing towards the object side, the 25
ing towards the image side, the ?fth component is a 30
single positive lens, the sixth component is a cemented
positive meniscus component consisting of a third con
Thlclmess Refractive Abbe
and
Index
Number
Separation
J1 =+447.7
fourth component is a meniscus array consisting of a
lens in the direction to the image side of the objective,
Radius
na=+142.3
fvx= 300.2
m=+ 96.9
fis=+518.0
_
.
References Cited in the ?le of this patent
UNITED STATES PATENTS
2,319,171
2,379,392
2,701,982
2,735,339
Warmisham et al. ____ _.. May 11,
Warmisham __________ __ June 26,
Angem'eux __________ __ Feb. 15,
Yoshikazu ____________ __ Feb. 21,
1943
1945
1955
1956
565,566
1,077,189
Germany ____________ .. Dec. 2, 1932
France ______________ __ Apr. 28, 1954
FOREIGN PATENTS