United States Patent [191
`Hansen
`
`[11] Patent Number:
`[45] Date of Patent:
`
`5,035,472
`Jul. 30, 1991
`
`[54] INTEGRATED MULTISPECI‘RAL MAN
`PORTABLE WEAPON SIGHT
`[75] Inventor:
`Charles L. Hansen, Fort Belvoir, Va.
`
`Primary Examiner-Bruce Y. Arnold
`Assistant Examiner-Martin _Lerner
`?gggney’ Agent’ or Flrm_Mllton W' Lee; Anthony T‘
`
`[73] Assignee: The United States of America as
`represented by the Secretary of the
`Army, Washington, DC.
`
`[21] Appl' NO’: 540’733
`[22] Filed:
`Jun. 20, 1990
`
`ABSTRACT
`[57]
`A multispectral sight integrated Onto a man portable
`rifle or stand alone weapon device for sighting the ri?e
`_or for surveillance by the device. The multispectral
`sight is contained in a unitary housing attached to or
`manufactured as an integral part of the man-pack
`weapon, such as from the forestock to the shoulder
`Stock Ofa ri?e’ the Sight is comprised of Common Obieo
`tive optics and eyepiece optics. Between the objective
`optics and eyepiece optics and optical devices for col
`lecting and separating input radiant energy into a plural
`ity of distinct wavelength spectrum channels, electronic
`processing means for processing a visible spectrum and
`for processing and converting to the visible spectrum a
`HEaLin?-ared Spectrum and a far infrared Spectrum in
`each of three spectrum channels, and optical devices for.
`
`_
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`
`[56]
`
`References Cited
`U S PATENT DOCUMENTS
`'
`'
`4,040.744 8/1977 Schertz et al. .................... .. 350/602
`4'669'8O9 6/1987 Pam’ at al- ~ ' ~ - ~
`- ' ~ ~ " 350/1"
`
`gebyer;
`' ' ' ' '
`4’822‘994 4/1989 Jorhrzisconeet aims...
`
`' ' ' ' "
`Iii-.1 350/12
`
`routing the outputs from the separate channels into the
`common eyepiece Optics for viewing of a Scene at an
`
`. . . .. 250/342
`4,902.128 2/1990 Siebecker et al. . . . . . .
`250/342
`4,9l7.490 4/1990 Schaffer. Jr. et al. .
`4,961.278 lO/l99O Johnson et a]. ..-. ....... ........ .. 350/12
`
`llght levels
`
`12 Claims, 5 Drawing Sheets
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`FOCAL PLANE
`ARRAY ELEC 24
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`BATTERY 2O
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`CRT
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`|2 TUBE 28
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`52
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`FLIR-1004
`FLIR Systems, Inc. vs CANVS Corporation
`Page 1 of 9
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`U.S. Patent
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`July 30, 1991
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`US. Patent
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`July 30, 1991
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`Sheet-4 of 5
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`FLIR-1004 / Page 5 of 9
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`U.S. Patent
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`July 30, 1991
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`Sheet 5 of 5
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`5,035,472
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`FLIR-1004 / Page 6 of 9
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`

`1
`
`INTEGRATED MULTISPECI'RAL MAN
`PORTABLE WEAPON SIGHT
`
`5,035,472
`2
`There are other exterior controls for adjusting the focus
`and for windage and elevation.
`The invention will be understood by reference to the
`following detailed description in view of the drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 illustrates a sniper ri?e on which the multi
`spectral sight is mounted within a detachable housing;
`FIGS. 2A, 2B, and 2C are views of the detachable
`housing of FIG. 1 respectively by angled side view,
`front objective end view, and top view;
`FIGS. 3A and 3B illustrate respectively a side eleva
`tional view of a ri?e having a unitary housing for the
`multispectral sight permanently molded thereon and a
`top view of the unitary housing;
`FIG. 4 is a schematic of the electrical and optical
`elements of one embodiment of- the multispectral sight;
`and
`FIG. 5 is a schematic of the electrical and optical
`elements of a second embodiment of the multispectral
`sight.
`
`The invention described herein may be manufac
`tured, used, and licensed by the US. Government for
`governmental purposes without the payment of any
`royalties thereon.
`
`BACKGROUND OF INVENTION
`1. Field
`The present invention relates to an integrated electro
`optical weapons sight, and especially to a multispectral
`sight integrated with a weapon which may be used
`either in daytime, twilight, or nighttime environments
`without changing the sight.
`2. Prior Art
`Daytime optical small weapon sighting is presently
`conducted by a variety of telescopes. A case in point is
`the Leopold and Stevens Ultra X-3 ri?e sight used on
`the US. Army’s M-24 sniper ri?e. The daytime perfor
`mance of this sight is acceptable. However, this sight
`must be dismounted from the ri?e in order to mount a
`sight with a different spectral response for other than
`daytime sighting, such as the near infrared and far infra
`red spectrums used respectively in the US. Army’s
`image intensi?ers (I2) and the forward looking infrared
`(FLIR) viewers.
`Boresight accuracy may not be maintained during
`?eld mounting and dismounting when various single
`spectrum sights or viewers are used in a mission requir
`ing multispectral observation. The total size and weight
`if all three sights are mounted on a weapon at the same
`time can become excessive and adversely affect the
`success of a military mission.
`
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`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`Refer to FIGS. 1, 2A, 2B, and 2C for perspective
`views of a unitary housing 10 mountable on a sniper
`ri?e 8, which can house the same multispectral sight as
`can the molded housing 11 as an integral portion of a
`combat ri?e 9, as shown by FIGS. 3A and 3B.
`The multispectral sight unitary housing 10 may be
`mounted on the sniper ri?e 8 in the usual manner, such
`as by coupling brackets or attaching at least two bands
`around both 10 and 8. Housing 10 has a top cover 10A
`through which the multispectral sight may be secured
`within 10 and then 10A is hermetically sealed to 10 after
`the sight has been boresighted with the ri?e. Housing 10
`has an objective optics end 14 and an eyepiece optics
`end 12. A rotary switch 30 may connect to electrical
`contact 31A for activating the visible spectrum of the
`multispectral sight, contact 31B for activating the near
`infrared spectrum, contact 31C for activating the far
`infrared spectrum, or contact 31D for activating both
`the near infrared spectrum and the far infrared spectrum
`simultaneously. A plurality of thumb nail rotary
`switches 36, 34, and 32, which are partly recessed in
`housing 10 to prevent inadvertent turning, respectively
`adjust scene brightness, contrast, and the brightness of
`the reticle. Other control knobs are knob 40 for adjust
`ing the focus, knob 42 for azimuth control, and knob 44
`for elevation control.
`FIGS. 3A and 3B should now be referred to for an
`illustration of the molded housing 11 used to integrated
`the multispectral sight (not fully shown) on ri?e 9. Pref
`erably, an optical bench (not shown) is first attached to
`ri?e 9 and then housing 11 is molded over the optical
`bench forming the shoulder stock 9A and the forestock
`98, including the trigger housing and upper sight por
`tions therebetween, onto ri?e 9. The sighting window
`15 and scalable access cap 11A are not placed on the
`opening on top of 11 until the various optics and the
`multispectral optical and electrical elements of the sight
`are mounted therethrough on the optical bench. A bat
`tery power source 20 is used to power the electrical
`elements. Leads from source 20 are fed through housing
`11 to be power the electrical elements. Leads from
`source 20 are fed through housing 11 to be connected to
`the electrical elements. Even though 20 is shown in the
`shoulder stock 9A it may be at any convenient location
`
`SUMMARY OF THE INVENTION
`The present invention is comprised of a multispectral
`sight which has a plurality of multispectral optical and
`electrical elements attachable in at least three distinct
`spectrum processing channels between common objec
`tive and eyepiece optics which are enclosed within a
`unitary housing that is permanently molded onto a US.
`Army ri?e or some other man portable type weapon.
`The molded housing preferably replaces the normal
`forestock and shoulder stock and the trigger housing
`therebetween. The housing has an elongated opening
`on the top through which the multispectral optical and
`electrical elements and objective and eyepiece optics
`are attachable to an optical bench which is attached to
`the man portable weapon. The multispectral sight is
`boresighted with the weapon and the elements secured
`tightly so as not to jar loose later. The elongated open
`ing may be hermetically sealed by a sighting window
`and an access cap. Prior to the window and cap being
`hermetically sealed, the internal portion of the housing
`is preferably pressurized with nitrogen gas to prevent
`moisture or outside matter from contaminating the opti
`cal and electrical elements.
`.
`The housing has a sequential rotary switch on the
`exterior thereof for selectively switching on a process
`ing means for each of the three distinct spectrum chan
`nels. These spectrums are preferably a visible spectrum
`for daytime viewing, a near infrared spectrum for twi
`light viewing, and a far infrared spectrum for thermal
`viewing at nighttime. A plurality of thumb nail rotary
`switches on the exterior of the housing controls the
`reticle brightness and the scene contrast and brightness.
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`proper focus of the visible image at the input thereto.
`within housing 11. The sighting window is elongated
`Value 50 may be a liquid crystal cell with power from
`and sloping to cover the full ?eld of view of the sight.
`power source 20 switchable thereto by rotary switch 30
`Items 30, 31A, 31B, 31C, 31D, 32, 34, 36, 40, 42 and
`connected to contact 31A to pass the visible spectrum
`44 are shown on the left side of housing 11 for conve
`therethrough or to block the passage of the visible spec
`nient manipulation by a person ?ring ri?e 9 from the
`trum therethrough if switch 30 is not connected to
`right shoulder. These items may also be placed on the
`contact 31A. When the visible spectrum passes through
`right side for a person ?ring ri?e 9 from the left shoul
`50 it passes directly through a third partially reflective
`der. Also, the position of these items on either side are
`beam splitter 54 and 56 and 12A for observation.
`not limited to the positions shown in FIGS. 3A and 3B.
`The near infrared spectrum channel 19C operates as a
`FIGS. 4 and 5 are schematic block diagrams of the
`twilight sight which overlaps with the visible spectrum,
`optical and electrical elements forming the multiple
`i.e. down to the 0.7um wavelength. The processing
`spectral channels between the objective optics and the
`means is preferably by a US. Army third generation
`eyepiece optics. It should be noted that FIGS. 4 and 5
`image intensi?er tube 28 which ampli?es and magni?es
`only differ in the two embodiments of the objective
`the near infrared image at the input thereto. A second
`optics. The multispectral radiant energy 6 from a typi
`fully re?ective mirror 52 at the output of 28 re?ects the
`cal scene enters the sight through sighting window 15
`magni?ed near infrared radiantenergy therefrom onto
`and through objective lens 14A along an objective op
`beam splitter 54, which is green re?ective, positioned at
`tics common optical axis 19. A ?rst partially re?ective
`the output of 50 along the common eyepiece optical axis
`beam splitter 16A, preferably made of germanium,
`19D with 56 and 12A for viewing by an observer. Ro
`passes the 3um through Sum and the 8um through l4um
`tary switch 30 activates 28 when 30 is connected to
`wavelengths of radiant energy of interest along a far
`infrared spectrum channel 19A for processing. Beam
`either contacts 31B or 31D.
`The thumb nail switches 32, 34, and 36 function as
`splitter 16A re?ects the shorter wavelength visible and
`follows. Switch 32 adjusts reticle brightness by adjust
`near infrared spectrums to a second partially re?ective
`ing the power from 20 to the reticle generator 22 which
`beam splitter 16B which passes the near infrared spec
`in turn feeds directly to 26 for observation. Switches 34
`trum of 0.7um through l.lum radiant energy of interest
`and 36 control the power to 28, 18, 24, and 26 to respec
`which is re?ected off a ?rst fully re?ective mirror 16C
`tively control the scene contrast and brightness. Knobs
`along a near infrared spectrum channel 19C for process
`40, 42, and 44 adjusts the focus, the azimuth or windage,
`ing. Beam splitter 16B re?ects the visible spectrum of
`0.5um through 0.8um through 0.8um radiant energy of
`and the elevation in the usual manner.
`FIG. 5 illustrates another objective optic which may
`interest along a visible spectrum channel 19B for pro
`be used in some circumstances of indirect viewing, that
`cessing. The visible spectrum channel 19B, and the near
`is periscopic viewing, using the multispectral sight. In
`infrared spectrum channel 19C are optically parallel
`this embodiment the incoming radiation 6 after passing
`with the far infrared spectrum channel 19A. All three '
`through the sighting window 15 is passed through a
`channels have separate processing means and means for
`multispectral beam splitter 58 onto a parobolic re?ector
`activating to process their respective radiant energy
`spectrums and whose processed signals exit therefrom
`optic 60, which may be re?ective or refractive, and is
`retrore?ected from 60, off 58 and through objective
`along a common eyepiece optical axis 19D for an ob
`lens 62 and off a third fully reflective mirror 64 and
`server to view through eyepiece lens 12A.
`along a common objective optic common optical axis 19
`A battery power source 20, which has appropriate
`toward the ?rst partially re?ective beam splitter 16A
`voltage of say 26 volts d.c., is used for activating the
`and proceeds as in the embodiment of FIG. 4.
`electrical elements within all the spectrum channels.
`The present multispectral sight provides a light
`The far infrared spectrum channel operates as a night
`weight, 24 hour per day, all weather electro-optic de
`time sight and is comprised of the readily available US.
`Army forward looking infrared sight electro-optic ele
`vice for use by the military in a sighting system.
`I claim:
`ments as processing means. These elements are an
`1. A multispectral sight apparatus integrated onto a
`imager lens 17 which collimates the infrared spectrum
`man portable type weapon for use in viewing a scene in
`onto an uncooled focal plane array 18 controlled by
`all ambient light level conditions, said apparatus com
`focal plane array electronics 24 in which the far infrared
`prised of:
`spectrum is converted to equivalent electrical signals
`common objective optics for collecting incoming
`which are in turn fed directly to a cathode ray tube
`display 26 for reconverting the electrical signals to the
`radiant energy from a variable light level scene and
`common eyepiece optics along a common eyepiece
`visible spectrum at the output of 26. The visible spec
`optical axis for viewing the scene;
`trum from 26 is re?ected offa fourth partially re?ective
`a plurality of multispectral optical and electrical ele
`beam splitter 56, which is red re?ective, positioned
`along axis 19D for passage through eyepiece lens 12A
`ments, said elements comprised of at least three
`distinct spectrum channels having optical parallel
`to an observer. The far infrared spectrum processing
`paths between said common objective optics and
`means, i.e. elements 18, 24, and 26, may be switched on
`eyepiece optics wherein each of said at least three
`by rotary switch 30 rotated to contact 31C or combined
`distinct spectrum channels process a distinct spec
`with the near infrared processing means by being ro
`trum of radiant energy therein, a plurality of radi
`tated to contact 31D.
`ant energy routing optical devices for collecting
`The visible spectrum channel 19B operates as a day
`and separating input radiant energy into each of
`time sight wherein the visible spectrum channel 19B
`optical axis is in' direct alignment with the eyepiece
`said at least three distinct spectrum channels and
`recombining the outputs of said channels along said
`optical axis 19D. A shutter means in the form of a light
`common eyepiece optical axis, and a processing
`control valve 50 is used in the processing means of the
`visible spectrum. Valve 50 is on the visible spectrum
`means comprised of a battery power source and
`channel 19B optical axis past the visible image plane for
`separate processing means in each of said at least
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`plurality of radiant energy routing optical devices fur
`three distinct spectrum channels for processing the
`ther comprised of a second fully reflective mirror posi
`radiant energy therein;
`tioned at the output of said image intensifier which
`means for selectively activating each of the at least
`reflects the magni?ed near infrared spectrum of energy
`three processing means according to the ambient
`onto a third partially re?ective beam splitter positioned
`light level of said scene being viewed in which said
`multispectral sight apparatus selectively operates
`on said common eyepiece optical axis at the output of
`said light control valve wherein said third partially
`in the visible spectrum for daylight viewing, in the
`reflective beam splitter passes said visible spectrum
`near infrared spectrum for twilight viewing, and in
`therethrough and is green re?ective for re?ecting said
`the far infrared spectrum for viewing in total dark
`near infrared spectrum therefrom along said common
`ness; and
`eyepiece optical axis and a fourth partially re?ective
`a unitary housing means for containing said common
`objective optics and eyepiece optics and said plu
`beam splitter positioned on said common eyepiece opti
`rality of multispectral optical and electrical ele
`cal axis at the output of said cathode ray tube display
`which passes said visible spectrum and said near infra
`ments within a housing and having said means for
`red spectrum therethrough along said common eye
`activating said processing means on the exterior of
`piece optical axis and is red re?ective to reflect said far
`said I housing.
`infrared spectrum therefrom along said common eye
`2. An apparatus as set forth in claim 1 wherein said at
`piece optical axis wherein all spectrums are selectively
`least three distinct spectrum channels are a- visible spec
`viewable through said common eyepiece optics.
`trum channel, a near infrared spectrum channel, and a
`8. An apparatus as set forth in claim 7 wherein said
`far infrared spectrum channel.
`means for selectively activating each of said at least
`3. An apparatus as set forth in claim 2 wherein said
`three processing means is comprised of a manually op
`visible spectrum channel processes radiant energy in the
`erable rotary switch on the exterior of said housing for
`0.5um to 0.8um range and said processing means is by a
`sequentially switching said power source to said light
`switchable light control valve is on the optical axis of
`control valve for processing only said visible spectrum,
`said visible spectrum channel optically parallel path and
`to said image intensi?er for processing only said near
`is switchable to said power source by said means for
`infrared spectrum, and said focal plane array electronics
`selectively activating said processing means.
`and cathode ray tube display for processing only said
`4. An apparatus as set forth in claim 3 wherein said
`far infrared spectrum, and to said image intensi?er and
`light control valve is a liquid crystal cell.
`said focal plane array electronics and cathode ray tube
`5. An apparatus as set forth in claim 2 wherein said
`display combined for processing said near infrared spec
`near infrared spectrum channel processes radiant en
`trum and far infrared spectrum simultaneously, said
`ergy in the 0.7um to 1.1um range and said processing
`means for selectively activating each of said at least
`means is a switchable image intensi?er having the near
`three processing means further comprised of a plurality
`infrared image plane at the input thereto on said near
`of manually operable thumb nail rotary switches for
`infrared spectrum channel optically parallel axis and is
`controlling reticle brightness and contrast and scene
`switchable to said power source by said means for selec
`brightness.
`tively activating said processing means.
`9. An apparatus as set forth in claim 8 wherein said
`6. An apparatus as set forth in claim 2 wherein said far
`common objective optics is comprised of a sighting
`infrared spectrum channel processes radiant energy in
`window transparent to said incoming radiant energy
`the Sum to Sum range and/or the 8um to l2um range
`and an objective lens both in optical alignment with said
`and said processing means is an imager lens which colli
`?rst partially re?ective beam splitter along said far
`mates the far infrared spectrum onto a focal plane array
`infrared spectrum channel optical axis.
`on said far infrared spectrum channel optically parallel
`10. An apparatus as set forth in claim 8 wherein said
`axis, wherein said focal plane array electronics converts
`common objective optics is comprises of a sighting
`said far infrared spectrum into electrical signals which
`window transparent to said incoming radiant energy
`are inputted to a cathode ray tube display which con
`and a multispectral beam splitter in optical alignment
`verts said electrical signals into a visible spectrum rep
`with a parabolic reflective optic in which said incoming
`lica of the original far infrared spectrum, and wherein
`radiant energy is passed through said multispectral
`said focal plane array and said cathode ray tube display
`beam splitter onto said parabolic re?ective optic, is
`are switchable to said power source by said means for
`selectively activating said processing means.
`re?ected back to and off of said multispectral beam
`splitter and through an objective lens, and is reflected
`7. An apparatus as set forth in claim 2 wherein said
`off a third fully re?ective mirror onto said ?rst partially
`plurality of radiant energy routing optical devices are
`re?ective beam splitter along said far infrared spectrum
`comprised of a ?rst partially re?ective beam splitter
`optical axis.
`which passes said far infrared spectrum along the opti
`cal axis of said far infrared spectrum channel through an
`11. An apparatus as set forth in claims 9 or 10 wherein
`said sighting window is made of zinc sul?de.
`imager lens which collimates said far infrared spectrum
`12. An apparatus as set forth in claim 1 wherein said
`on said focal plane array and reflects said visible spec
`housing is manufactured about said man portable
`trum and said near infrared spectrum therefrom onto a
`second partially re?ective beam splitter which passes
`weapon from a forestock to a shoulder stock in which
`said weapon has an optical bench thereon for mounting
`said near infrared spectrum therethrough and reflects
`said plurality of multispectral optical and electrical
`said visible spectrum into a light control valve in said
`elements thereon through an elongated ‘opening on the
`visible spectrum channel whose optical axis is in direct
`top of said housing, said plurality of multispectral opti
`alignment with said common eyepiece optical axis at the
`‘cal elements are boresighted with said man portable
`output of said light control valve; said visible spectrum
`channel optical axis is parallel with said far infrared
`weapon, said housing having a sealable access cap
`spectrum channel optical axis, wherein said near infra
`wherein said sighting window and said access cap are
`hermetically sealed over said elongated opening for
`red spectrum is re?ected off a ?rst fully re?ective mir
`permanently integrating said multispectral sight appara
`ror into an image intensi?er tube in said near infrared
`spectrum channel whose optical axis is also in parallel
`tus to said man portable weapon.
`with said visible spectrum channel optical axis, said
`#
`t
`It
`it
`It
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`FLIR-1004 / Page 9 of 9
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