вход по аккаунту


Патент USA US2406213

код для вставки
Patented Aug. 20, 1946
2,406,213- *- ~
' ' ~Bausch & Loinb‘OpticaL Company,
N. Y" a corporation of New ‘York
; Application‘ February 26 1944,.SerialNo. 524,030
' This ‘invention relates to optical v‘instruments
of the telescoping tubes,.any dust entering the
and moreparticularly to a dust shield‘ for micro
‘scopes, telescopes, and the like.
eyepiece tube will be, con?ned to‘the area of‘ the
face encompassed by‘the gasket and‘ will thus
""In the ‘use of microscopes, it is common prac
tice to‘ employ‘ several eyepieces forsecuring dif~
be prevented from passing into the body of the
instrument. ‘The dust will ‘thus be localized 'in
a relatively small space on the face of the prism
ferent"magni?cationsfof the. image of the ob
ject an'dyforthis purpose, the eyepieces can be
andmaybe readilyrem'oved through the'eyepiece
interchangeably mounted in the eyepiece tubes
' secured to the body .of the microscope. ‘In pris
Theseand other objects and advantages reside
‘matic microscopes,‘ the end of each tube is gen 10
in certain novel features of construction, arrange
erally mounted in the body of the microscope in
,ment,.and combination of parts as will herein
's'pace'd'relation to the exit "face ‘of one of the
“after he more fully set forth and pointed out. as
prisms of the prism system. Upon removal and
the ‘speci?cation ‘proceeds.
replacement'of ‘the‘eyepieces, dust in the air sur~
Inthe drawing:
‘ I
rounding ‘thee‘xterior end of the eyepiece tube
of a vertical section
"enters the tube andilodges on the prisms and
of one body unit of a binocular microscope'hav
ing a dust shield’ embodying my invention.
'This dust‘is a source/of annoyance to the
‘Fig. ‘2 is‘ a fragmentary ‘sectional View showing
microscopist for‘ the dust castsshadows in ~the
the "dust shield carried by the‘lower' end of the
‘image ?eldan'd reduces illuminati'on'of the image
when‘ lodged onfthe. transmittingfaces of the
“prisms and ‘lenses. Oil' particles are ‘ particularly
objectionable if they adhere to the re?ecting faces
of the prisms for such‘ particles often distort the
image due to the differences in the indices of
refraction of the oil and the glass of the prism.
To remove the dust, the microscope must be
taken apart and the dust brushed from the prisms
and objective. In most cases, the disassembling
and reassembling of the microscope requires a
factory operation for the exactitude with which
the optical elements must be necessarily held in‘
the optical axis of the instrument requires a
skilled workman to perform this operation or
elsethe optical elements may be moved out of 35
their optical alignment and the utility of the
instrument be materially impaired. Whether or
not this operation be performed by a skilled work
man or the microscopist, the elimination of the
dust from the. instrument is a tedious and pains 40
taking task due to the tendency of the dust to
settle back on the cleaned surfaces of the optical
elements of the microscope.
It is the principal object of the present inven- '
tion to provide in a microscope or the like, a
shield which effectively prevents the entrance of
dust into the body of the instrument through the
eyepiece tube. To accomplish the result desired,
the interior end of the eyepiece tube‘ adjacent the
eyepiece tube and engaging the upper portion'of
the prism.’
{Referring to the drawing, it will be seen‘that
the invention is there ‘shown, ‘for the purposes
of illustration only, as ‘being embodied in'a body
unit of a binocular microscope of the Greenough
type, designated generally at Hi. It will be seen
that generally speaking, the microscope com
prises a casing or housing I l inwhich is mounted
a prismatic reversing system comprising a pair
of prisms l2 and IS. The bottom wall I4 of the
casing is formed with a downwardly extending
annular ?ange [5 into which is threaded the ob
jective tube I 6 carrying an objective IT. The
other end of the casing II is closed by a ‘cap
l8 having a threaded opening receiving one end .
of an eyepiece tube IS.
The eyepiece tube is
securely held in the cap [8 by threading the tube
into the opening in the cap until the ?ange 2|
of the tube is ?rmly seated upon the edge surface
de?ning the opening in the cap.
In prismatic instruments, such as binocular
microscopes of the type shown, the prism assem
bly is often carried within a casing such as shown
at H in spaced relation to the eyepiece tube. In
the interchange of eyepieces to effect different
magni?cations of the object and also in the use’
of the microscope, dust and oil particles fre
quently enter the eyepiece tube and pass there
through into the casing to lodge on the prism
exit face of one of the prisms telescopically re 50 transmitting and reflecting faces and also on the
ceives a tube of such a length that a gasket of
back surface of the objective. Dust on the trans
rubber, or other resilient material carried by the
end face thereof engages the exit face of the
mitting faces casts shadows in the image ?eld
and reduces illumination of the image while oil
prism. As the gasket is held tightly against the
face of the prism by the frictional engagement 55 particles often adhere to the re?ecting faces of
the prism causing distortion of the image due to
ing through the eyepiece tube and thereby inf
sures maximum illumination and the true form
of the image. 3T0 this end, the-dust shield com:
prises a tubular "member 22 telescopically engag-j
ing the extremity of the eyepiece tube [9. The
end of the member 22 adjacent the prism I2 is"
for-med with a ?ange 23 underlying the endof; _ _
~ the eyepiece tube 19,
I am able to attain the objects of my invention l
The dust shield of the present invention e?ece
tively prevents the passage of dust into the case
From the foregoing, it will be apparent that
the variation in the indices of refraction of the
‘ oil and the glass of the prism.
bottomgsurface of the
and provide a dust shield for optical instruments
preventing passage of dust into the casing
through the eyepiece tube. While the dust shield
has been shown and described with reference to
a prismatic microscope, its use should not be lim
ited thereto forthe shield maypbeiused in any
-'optical instrument wherem an optical element is
,mounted closely adjacent‘ the eyepiece tube and'
_ can be used to form an element of the seal. For
*this'purpose, various modi?cations can be made
without; departing from the spirit of my inven
?ange 23 is formed with a eircumferentialy'groove, ' tion as de?ned in the‘ appended claims.
“adapted to receive an annular ‘gasket 25 of - "
I claim:
rubber, or like elastic material, 7 whichfwhile 15 a - 1. An optical instrument having in combina
?rmly'seated in~the groove, extends outwardly ' 'tion a casing provided with an aperture, an op-'
therefrom to engage the transmitting face 26
of the prism l2. The gasket 25 is held tightly j'
tical element mounted in the casing, said element
having a surface spaced from and in alignment
against the face 26 of the prism l2 bythe fric
rwithrthe aperture, a lens tube mounted in said
tional engagement, of the tubular member 22
aperture and having an end: projecting. into the
casing adjacent to. but out of, contact with said
.It will
the eyepiece
be apparent
tube‘ that
l9“, thegasket
v circum
surface, a tubular member telescopically mounted V
scribes an annular area ‘on
on said end, and gasket means carried by'said
.prism l2 and, by so doing, ‘e?ectually seals the
member and adapted to‘ engage the surface'of
interior of‘ the casing from dust passing into the
the element whereby the passage of dust through
eyepiece tube.’ The/dust willthusj bevlocalized
the tube and into the casing is prevented.‘
on the face of
2. An optical instrument comprising a casing
?ned by the opening in thergasketand'may be
having an aperture, an optical element- mounted
readily , removed from the face of the prism
within the vcasing in‘ alignment with the aper
through the eyepiece tube in any desired manner. 30 ture, a lens tube threadedly mounted on the eas
In theassembly of the. dust shield, with the
ing and having an end extending .through the
microscope, the cap is removed'and the tubular
aperture and into the casing inproximity to a
member 22, slid over the end ofthe eyepiece tube
surface of ‘the element, a tubular member slidably ‘
H). The cap is thenrreplaced on the casing‘ and
mounted on the outer surface of‘the rendiof the
then the ?ange 23 is pushed’ downwardly by any
tube, said member having an integral ‘?ange,
suitable toolv passe'drinto thetube l9 until the
gasket means carried on said ?ange, said member
gasket is seated‘ upon the
being‘ adjustably positioned on the tubegto bring ‘ .Y
As the tubular member '22,‘ telescopically re
the gasket means into contact with the. surface
ceives theeyepiece tube l9, the, dust shield does
the’ element whereby the passage [of dust
not interfere with the movement of eyepieces ‘of 40 ,of
through the‘ tubeand ; into the Leasing is preé
substantial length in the eyepiece tube. ‘1 Also,“
_ the opening in the ?ange 23 is of sumcient di
ameter to prevent vignetting.
,' JG‘EQBGE 3.; antigen‘; 2
Без категории
Размер файла
352 Кб
Пожаловаться на содержимое документа