(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`
`(19) World Intellectual Property Organization
`International Bureau
`
`(43) International Publication Date
`1 November 2001 (01.11.2001)
`
`• I IIIII IIIIIIII II IIIIII IIIII IIII I II Ill lllll lllll lllll lllll llll 1111111111111111111
`
`(10) International Publication Number
`WO 01/81956 Al
`
`PCT
`
`(51) International Patent Classification 7:
`
`G02B 5/08
`
`(21) International Application Number:
`
`PCT/USOl/13283
`
`(22) International Filing Date:
`
`24 April 2001 (24.04.2001)
`
`(25) Filing Language:
`
`(26) Publication Language:
`
`English
`
`English
`
`(30) Priority Data:
`09/551,676
`09/733,410
`
`24 April 2000 (24.04.2000) US
`11 December 2000 (11.12.2000) US
`
`(81) Designated States (national): AE, AG, AL, AM, AT, AU,
`AZ, BA, BB, BG, BR, BY, BZ, CA, CH, CN, CO, CR, CU,
`CZ, DE, DK, DM, DZ, EE, ES, FI, GB, GD, GE, GH, GM,
`HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK,
`LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX,
`MZ, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL,
`TJ, TM, TR, TT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZW.
`
`(84) Designated States (regional): ARIPO patent (GH, GM,
`KE, LS, MW, MZ, SD, SL, SZ, TZ, UG, ZW), Eurasian
`patent (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), European
`patent (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE,
`IT, LU, MC, NL, PT, SE, TR), OAPI patent (BF, BJ, CF,
`CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG).
`
`(71) Applicant and
`(72) Inventor: PLATZER, George, E., Jr. [US/US]; 424 Cy-
`press Road, Rochester Hills, MI 48309 (US).
`
`Published:
`with international search report
`
`(74) Agents: NEMAZI, John, E. et al.; Brooks & Kushman,
`1000 Town Center, 22nd floor, Southfield, MI 48075 (US).
`
`For two-letter codes and other abbreviations, refer to the "Guid(cid:173)
`ance Notes on Codes and Abbreviations" appearing at the begin(cid:173)
`ning of each regular issue of the PCT Gazette.
`
`--
`
`-
`
`(54) Title: COMPOUND AUTOMOTIVE REARVIEW MIRROR
`
`;;;;;;;;;;;;-------------------------------------------
`-;;;;;;;;;;;;
`
`!!!!!!!!!!
`
`r··
`t
`12
`
`54
`
`(57) Abstract: A composite mirror in(cid:173)
`cludes a main viewing mirror (40) and
`an auxiliary blindzone viewing mirror
`(36) juxtaposed to expose the vehicle
`blindzone to the operator.
`
`SMR USA
`Exhibit 1013
`Page 001
`
`

`

`WO 01/81956
`
`PCT /USOl/13283
`
`Compound Automotive Rearview Mirror
`
`Field of Invention
`
`5
`
`The present invention relates generally to mirrors having multiple
`
`surfaces of differing magnification and, particularly, to the application of such
`
`mirrors as external side rearview automotive operator aides.
`
`10
`
`Background of the Invention
`
`Originally, motor vehicles, particularly passenger cars, did not have
`
`mirrors to assist the driver. Early in this century however, both inside and
`
`outside mirrors were added to automotive vehicles to provide rearward and
`
`15
`
`limited lateral visibility. As the number of vehicles and driving speeds
`
`increased, rearward visibility became ever more important.
`
`Today, all passenger cars have a mirror centrally located inside the
`
`vehicle. This mirror is the primary mirror. It provides a wide viewing angle,
`
`20
`
`giving an excellent view to the adjacent lanes at a distance of two or more car
`
`lengths to the rear. However, it is deficient in that it is unable to view the
`
`adjacent lanes at distances of less than one to two car lengths to the rear. In
`
`an effort to eliminate this deficiency and to provide rearward visibility when the
`
`rear window is blocked, outside mirrors were added to vehicles.
`
`25
`
`Presently, passenger cars are required by law to have a unit
`
`magnification outside rearview mirror on the driver's side. A unit magnification
`
`mirror is a plane mirror which produces the same size image on the retina as
`
`that which would be produced if the object were viewed directly from the same
`
`30
`
`distance. Furthermore, as provided in Federal Motor Vehicle Safety Standard
`
`111 (FMVSS 111 ), "The mirror shall provide the driver a field of view of a level
`
`road surface extending to the horizon from a line perpendicular to a
`
`longitudinal plane tangent to the driver's side of the vehicle at the widest point,
`
`extending 8 feet out from the tangent plane 35 feet behind the driver's eyes,
`
`SMR USA
`Exhibit 1013
`Page 002
`
`

`

`WO 01/81956
`
`PCT/USOt/13283
`
`with the seat in the rear most position." FMVSS 111 thus effectively
`
`determines the size of the mirror, which a manufacturer must provide. The
`
`size will vary among different manufacture's vehicles because of the
`
`placement of the mirror on the vehicle with regard to the driver's seat location.
`
`5
`
`Unfortunately, outside mirrors meeting FMVSS 111 still do not provide
`
`adequate adjacent lane visibility to view cars that are in the range of one car
`
`length to the rear. That is, a blindzone exists where a vehicle is not visible in
`
`either the inside mirror or the outside mirror. Even a glance over the shoulder
`
`10 may not be adequate to observe a vehicle in the blindzone. For many
`
`vehicles, the door pillar between the front and rear doors obscures the view to
`
`the blindzone. Furthermore, this obstruction is not obvious to most drivers,
`
`and they may assume that the "over the shoulder glance" has allowed them to
`
`see the blindzone when in reality it has not.
`
`15
`
`Rearward vision in automobiles is mathematically described in a paper
`
`published by the Society of Automotive Engineers (SAE) in 1995. That paper
`
`is designated as SAE Technical Paper 950601. It is entitled, The Geometry of
`
`Automotive Rearview Mirrors - Why Blindzones Exist and Strategies to
`
`20 Overcome Them, by George Platzer, the inventor of the present invention.
`
`That paper is hereby incorporated by reference.
`
`A common method of overcoming the blindzone is to add a spherically
`
`convex blindzone-viewing mirror to the required plane main mirror.
`
`25
`
`Spherically convex mirrors provide a wide field of view, but at the penalty of a
`
`reduced image size. However, this may be acceptable if the mirror is only
`
`used to indicate the presence of a vehicle in the blindzone and it is not used
`
`to judge the distance or approach speed of vehicles to the rear. Simply
`
`placing a round segment of a convex mirror on the main mirror surface, as is
`
`30
`
`commonly done with stick-on convex mirrors, does not solve the problem.
`
`Doing so can provide a view to the rear which includes the blindzone, but it
`
`will also show much of the side of the car, the sky and the road surface, which
`
`are distracting and extraneous to the safe operation of the vehicle. What is
`
`required is a convex blindzone-viewing mirror that shows the driver primarily
`
`2
`
`SMR USA
`Exhibit 1013
`Page 003
`
`

`

`WO 01/81956
`
`PCT /USOl/13283
`
`only the blindzone. In this way, if the driver sees a vehicle in the blindzone(cid:173)
`
`viewing mirror, he knows it is unsafe to move into the adjacent lane. All
`
`extraneous and distracting information should be removed from the blindzone(cid:173)
`
`viewing mirror. Furthermore, by eliminating the irrelevant portions of the
`
`s
`
`bull's-eye mirror, the remaining portion can have a larger radius of curvature,
`
`thereby increasing the image size for the given amount of area that is to be
`
`allocated to the convex mirror.
`
`Other problems with add-on mirrors are that they:
`
`10
`
`• may interfere with the requirements of FMVSS 111;
`
`• may substantially decrease the plane main mirror viewing angle;
`
`•
`
`interfere with cleaning, especially when there is ice on it; and
`
`• appear as an unsightly excrescence on the main mirror. A blindzone(cid:173)
`
`viewing mirror that is provided by a car manufacturer must not appear
`
`15
`
`to be an afterthought, but rather an integral part of the mirror.
`
`Summary of the Invention
`
`One object of the present invention is to provide a unit magnification
`
`20 main mirror, which meets the requirements of FMVSS 111 and simultaneously
`
`provides a blindzone-viewing mirror having a magnification of less than unity
`
`that is in application able to show an automobile driver's side blindzone.
`
`Another object of the invention is to provide a less than unit
`2s magnification mirror that meets the requirements of FMVSS 111 on the
`passenger's side and simultaneously provides a blindzone- viewing mirror
`
`having a magnification of less than unity that is able to show the driver the
`
`blindzone on the passenger's side.
`
`30
`
`Yet another object of the invention is to provide a mirror having a
`
`combination of two surfaces of different magnification that is not objectionable
`
`in appearance.
`
`3
`
`SMR USA
`Exhibit 1013
`Page 004
`
`

`

`WO 01/81956
`
`PCT/USOl/13283
`
`Still another object of the invention is to provide a mirror having a
`
`combination of two surfaces of different magnification that is inexpensive and
`
`easy to manufacture.
`
`5
`
`In a preferred embodiment of the invention, a less than unit
`
`magnification mirror is located in the upper and outer region of a unit
`
`magnification mirror, and it is optimized in size and orientation to provide
`
`primarily only a view of the blindzone while leaving the region surrounding it
`
`available to meet the requirements of FMVSS 111. The less than unit
`
`10 magnification mirror is integral with the unit magnification mirror.
`
`In yet
`
`another preferred embodiment of the invention, the unit magnification main
`
`mirror includes means operative to selectively vary the intensity of the
`
`reflection from the main mirror while maintaining a relatively fixed reflection
`
`intensity characteristic of the auxiliary mirror.
`
`15
`
`Brief Description of the Drawings
`
`In the drawings, wherein for clarity certain details may be omitted from
`
`one or more views:
`
`20
`
`Figure 1, is a plan view of an automobile on a three-lane highway
`
`depicting the field of view of the outside mirrors and the blindzones;
`
`Figure 2, is a diagram showing the requirements of FMVSS 111 for the
`
`horizontal field of view of the driver's outside mirror;
`
`Figure 3, is a diagram showing the requirements of FMVSS 111 for the
`
`25
`
`vertical field of view of the driver's outside mirror;
`
`Figure 4, is an image of the road as seen in the driver's outside mirror
`
`showing the effect of the requirements of FMVSS 111 on the horizontal width
`
`and the vertical height of the mirror;
`
`Figure 5, is a perspective drawing showing how a less than unit
`
`30 magnification mirror can be placed on the driver's outside mirror to avoid
`conflicting with the requirements of FMVSS 111 and yet provide a wide angle
`
`mirror to observe the blindzone;
`
`Figure 6, is a front view of the mirror of Figure 5;
`
`4
`
`SMR USA
`Exhibit 1013
`Page 005
`
`

`

`WO 01/81956
`
`PCT/USOt/13283
`
`Figure 7, is side sectional view of the mirror of Figure 6 in the plane
`
`along line 7-7 in the direction of the arrows showing the proper location of the
`
`center of the sphere on which
`
`the surface of the blindzone mirror lies, so as to produce vertical centering of
`
`5
`
`the image of a vehicle that is in the blindzone;
`
`Figure 8, is a top sectional view of the mirror of Figure 6 in the plane
`
`along line 8-8 looking in the direction of the arrows showing the proper
`
`location of the center of the sphere
`
`on which the surface of the blindzone mirror lies, so as to produce horizontal
`
`10
`
`centering of the image of a vehicle that is in the blindzone;
`
`Figure 9, is a plan view of a two-lane highway showing a vehicle in the
`
`right lane equipped with the mirror of Figure 5 and four positions of an
`
`overtaking vehicle in the left lane;
`
`Figure 1 Oa, shows the image of an overtaking vehicle in Figure 9, in a
`
`15 mirror like that of Figure 5;
`
`Figure 1 Ob, is like Figure 1 Oa except that the overtaking vehicle is
`
`farther to the rear; Figure 1 Oc, is like Figure 1 Ob except that the overtaking
`
`vehicle is farther to the rear;
`
`Figure 1 Od, is like Figure 1 Oc except that the overtaking vehicle is
`
`20
`
`farther to the rear;
`
`Figure 11, is a front view of a driver's side mirror embodying the
`
`teachings of this invention;
`
`Figure 12, is an enlarged top sectional view of the mirror of Figure 11
`
`taken in the plane along line12-12 in the direction of the arrows.
`
`25
`
`Figure 13, is a top view of a circular segment of a spherical mirror;
`
`Figure 14, is a side view of the mirror of Figure 13;
`
`Figure 15, is a top view of the mirror of Figure 13 wherein the mirror
`
`has been cut into square elements;
`
`Figure 16, is a side sectional view of the mirror of Figure 15 taken in
`
`30
`
`the plane along line 16-16 looking in the direction of the arrows;
`
`Figure 17, depicts how the mirror of Figures 15 and 16 can be
`
`rearranged into a planar array of reflecting facets;
`
`Figure 18, shows how light is reflected from the mirror of Figure 14;
`
`5
`
`SMR USA
`Exhibit 1013
`Page 006
`
`

`

`WO 01/81956
`
`PCT/USOl/13283
`
`Figure 19, shows how light reflected from the mirror of Figure 17
`
`simulates the reflections from the mirror of Figure 14;
`
`Figure 20, shows a mirror alternatively embodying the teachings of the
`
`invention;
`
`5
`
`Figure 21, is an enlarged side sectional view of the mirror of Figure 20
`
`taken in the plane along line 21-21 and looking in the direction of the arrows;
`
`Figure 22, is a diagram comparing a directly reflected ray from a front
`
`surface mirror to a refracted ray from a second surface mirror;
`
`Figure 23, is a diagram comparing the radius of curvature of a front
`
`10
`
`surface mirror to the radius of curvature of a second surface mirror;
`
`Figure 24, shows another embodiment of a mirror using the teachings
`
`of the invention;
`
`Figure 25, shows an enlarged top sectional view of the mirror of Figure
`
`24 in the plane along line 25-25 looking in the direction of the arrows;
`
`15
`
`Figure 26, shows yet another embodiment of a mirror employing the
`
`teachings of the invention;
`
`Figure 27, is an enlarged top sectional view of the mirror of Figure 26 in
`
`the plane along line 27-27 looking in the direction of the arrows;
`
`Figure 28, shows still another embodiment of a mirror employing the
`
`20
`
`teachings of the invention;
`
`Figure 29, is an enlarged top sectional view of the mirror of Figure 28 in
`
`the plane along line 29-29 and looking in the direction of the arrows;
`
`Figure 30, shows another embodiment of a mirror using the teachings
`
`of the invention;
`
`25
`
`Figure 31, is an enlarged top sectional view of the mirror of Figure 30
`
`taken in the plane along line 31-31 looking in the direction of the arrows;
`
`Figure 32, shows yet another mirror embodying the teachings of this
`
`invention;
`
`Figure 33, is an enlarged top sectional view of the mirror of Figure 32
`
`30
`
`taken in the plane along line 33-33 and looking in the direction of the arrows;
`
`Figure 34, shows another mirror incorporating the teachings of the
`
`invention;
`
`Figure 35, shows still another mirror incorporating the teachings of the
`
`invention;
`
`6
`
`SMR USA
`Exhibit 1013
`Page 007
`
`

`

`WO 01/81956
`
`PCT/USOt/13283
`
`Figure 36, is a front view of a prior art mirror having variable reflectivity;
`
`Figure 37, is a top sectional view of the mirror of Figure 36 in the plane
`
`along line 37-37 looking in the direction of the arrows;
`
`Figure 38, is a front view of a variable reflectivity mirror embodying the
`
`5
`
`present invention;
`
`Figure 39a, is a top sectional view of the mirror of Figure 38 in the
`
`plane along line 39-39 looking in the direction of the arrows;
`
`Figure 39b, shows another embodiment of a variable reflectivity mirror
`
`employing the teachings of the present invention similar in a number of
`
`10
`
`respects to the embodiment of Figure 39a;
`
`Figure 40, is a front view of an alternative embodiment variable
`
`reflectivity mirror;
`
`Figure 41, is a top sectional view of the mirror of Figure 40in the plane
`
`along line 41-41 looking in the direction of the arrows;
`
`15
`
`Figure 42, is a front view of another alternative embodiment variable
`
`reflectivity mirror;
`
`Figure 43, is a top sectional view of the mirror of Figure 42 in the plane
`
`along line 43-43 looking in the direction of the arrows;
`
`Figure 44, is a front view of another alternative embodiment variable
`
`20
`
`reflectivity mirror similar in a number of respects to the embodiment of Figures
`
`42 and 43;
`
`Figure 45, is a top sectional view of the mirror of Figure 44 in the plane
`
`along line 45-45 looking in the direction of the arrows;
`
`Figure 46, is a front view of another alternative embodiment variable
`
`25
`
`reflectivity mirror;
`
`Figure 47a, is a broken, top sectional view of the mirror of Figure 46 on
`
`an enlarged scale in the plane along line 47-47 looking in the direction of the
`
`arrows;
`
`Figure 47b, shows another embodiment of a variable reflectivity mirror
`
`30
`
`similar in a number of respects to the embodiment of Figure 47a;
`
`Figure 4 7c, shows yet another embodiment of the variable reflectivity
`
`mirror similar in a number of respects to the embodiment of Figure 47a;
`
`7
`
`SMR USA
`Exhibit 1013
`Page 008
`
`

`

`WO 01/81956
`
`PCT/USOl/13283
`
`Figure 48, is a front view of another alternative embodiment variable
`
`reflectivity mirror similar in a number of respects to the embodiment of Figures
`
`46 and 47a;
`
`Figure 49, is a top sectional view of the mirror of Figure 48 in the plane
`
`5
`
`along line 49-49 looking in the direction of the arrows;
`
`Figure 50, is a front view of another alternative embodiment variable
`
`reflectivity mirror similar in a number of respects to the embodiment of Figure
`
`46 and 47c;
`
`Figure 51, is a top sectional view of the mirror of Figure 50 in the plane
`
`10
`
`along line 51-51 looking in the directions of the arrows;
`
`Figure 52, is a front view of yet another alternative embodiment
`
`variable reflectivity mirror;
`
`Figure 53, is a top sectional view of the mirror of Figure 52, in the plane
`
`along line 53-53 looking in the direction of the arrows;
`
`15
`
`Figure 54, is an exploded perspective view of the mirror of Figure 52;
`
`Figure 55 is a front view of another embodiment of a mirror employing
`
`the teachings of this invention;
`
`Figure 56 is an enlarged sectional view of the mirror of Figure 55 taken
`
`along section line 56-56 in the direction of the arrows;
`
`20
`
`Figure 57 is an exploded view of a mirror assembly of the present
`
`invention; and
`
`Figure 58 is a cross-sectional side view of a mirror and bezel.
`
`Detailed Description of the Preferred and Alternative Embodiments
`
`25
`
`Referring now in greater detail to the drawings, Figure 1 shows a mid(cid:173)
`
`sized passenger car 10 in the middle lane of a three-lane highway with 12-foot
`
`wide lanes. The vehicle 10 is equipped with a driver's side outside mirror 12.
`
`The driver's eyes are shown centered at point 14, from which the driver has a
`
`30
`
`field of view to the rear in the horizontal plane encompassing the acute angle
`
`formed by lines 16 and 18. Line 20 defines the rearward limit of the driver's
`
`peripheral vision when looking at mirror 12. Thus, the area bounded by lines
`
`18 and 20 is a blindzone, shown crosshatched, which cannot be observed in
`
`either the driver's direct forward vision or indirectly in the mirror.
`
`8
`
`SMR USA
`Exhibit 1013
`Page 009
`
`

`

`WO 01/81956
`
`PCT/USOl/13283
`
`SAE Technical Paper 950601 describes the horizontal field of view of a
`
`plane mirror in a mathematical equation as a function of the mirror's
`
`dimensions and the position of the eyes relative to the mirror. Typically, the
`
`5
`
`angle 8 subtended by lines 16 and 18 is in the order of 15° to 20 °. Angle 8 is
`
`given by Eq. 1, and it is,
`
`e = 2tan-1[WCOSA + D:
`
`~ 0
`2s[ + Si
`
`0
`
`!
`
`Eq.1
`
`where:
`
`w = mirror width;
`
`D = interpupillary distance;
`
`SL = the longitudinal distance along the axis of the vehicle form
`
`the driver's eyes to the center of the mirror;
`
`ST= the transverse distance perpendicular to the longitudinal
`
`axis from the driver's eyes to the center of the mirror; and
`A=% tan - 1 (sT/sL),
`
`10
`
`15
`
`As described in SAE Technical Paper 950601, the peripheral vision line
`
`20 cannot be precisely located. It depends on the location of the drivers' eyes
`
`relative to the mirror 12 and several other factors. For example, Burg (Journal
`
`of Applied Psychology, Vol.5, No. 12, 1968) has shown that the angular extent
`
`20
`
`of peripheral vision is a function of age. At age 20 it extends 88° from
`
`straight-ahead to the side. At 70 years, this angle has dropped to 75°.
`
`Angle <j> in Figure 1 is the angle of the peripheral vision line 20 relative
`
`to line 22, which is perpendicular to the longitudinal axis of vehicle 10.
`
`25
`
`Typically this angle will be in the range of 40 degrees.
`
`Figure 2 shows the requirement imposed on the width of mirror 12 by
`
`FMVSS 111. As previously stated, the mirror 12 must be able to show a
`
`point, as 24, which is 244 cm (8 feet) out from a plane 26 tangent to the side
`
`30
`
`of the vehicle and 1067 cm (35 feet) behind the driver's eyes with the seat in
`
`the rear most position. Point 28 is 1067 cm behind the driver's eyes and in
`
`9
`
`SMR USA
`Exhibit 1013
`Page 010
`
`

`

`WO 01/81956
`
`PCT /USOl/13283
`
`plane 26. Points 24 and 28 are on the road surface. Angle 8 in Figure 2 is
`
`obviously,
`
`e = tan-'[ s, !~:67 l
`
`Eq.2
`
`Angle 8 has a value of about 11.5° for almost any passenger car, and the
`
`s
`
`variation in 8 produced by variations in SL is a second order effect. Hence, the
`
`width of the mirror required by FMVSS 111 can be calculated by solving
`
`Equation 1 for w. Then,
`
`10
`
`8
`2~ s~ + s~
`- D
`tan
`2
`w= - - -~ -~ -
`COSA
`
`Eq.3
`
`Angle 8 in this case is equal to 11.5°. Using values of SL= 45.7cm, Sr=
`
`70cm, and D = 6.4cm, w is found to be 9.4cm. This value can vary
`
`significantly among vehicles, since in Eq.3, SL and Sr variations no longer
`
`1s
`
`produce only second order effects as in Eq. 2. In practice, vehicle
`
`manufactures will specify mirror widths in excess of the FMVSS 111
`
`requirements to further reduce the blindzone size.
`
`Figure 3 shows the requirements imposed on the vertical dimension of
`
`20 mirror 12 by FMVSS 111. In the vertical plane, vision is monocular since the
`
`eyes are not separated as they are in the horizontal plane. SAE Technical
`
`Paper 950601 shows that for monocular vision, the interpupillary distance D
`
`drops out of Equation 1, so that it becomes,
`
`25
`
`Then,
`
`Eq.4
`
`Eq.5
`
`e
`,
`~ ,
`2s~ + s; tan-
`w =
`2
`
`COSA
`
`10
`
`SMR USA
`Exhibit 1013
`Page 011
`
`

`

`WO 01/81956
`
`PCT/USOI/13283
`
`In Figure 3, h is the height in cm of mirror 12 above the ground, and it can
`
`vary significantly from a sports car to a sedan to a van. Angle 8v is the angle
`
`that determines what the vertical dimension, Wv, of mirror 12 must be, in
`
`5
`
`conjunction with the distance of the eye from the mirror. Angle 8v replaces
`angle e in Equation 5 when calculating the vertical dimension of the mirror.
`Applying Equation 5 to the required vertical dimension of the mirror, Wv ,
`
`8
`2~s~ + s~ tan
`v
`2
`Wv = --C-0-SAy __ _
`
`Eq.6
`
`10 where:
`
`Sv = vertical distance in the vertical plane from the eye to the
`
`mirror;
`
`Av=% tan -1(Sv/SL); and
`h J
`.
`Sv + 1067
`
`v= an
`t
`8
`-1 (
`
`Substituting measured values of h, SL, and Sv from one mid-size passenger
`
`15
`
`car gave a value for Wv of 6.4cm.
`
`The FMVSS 111 requirement for the vertical dimension of the mirror is
`
`only a minimum, and it does not provide a satisfactory mirror. Drivers usually
`
`set their mirrors so that if the car is on a straight and level road, the horizon
`
`20 will be in about the center of the mirror. This means that if point 24 is to be
`
`visible with the horizon centered, the mirror should be about 12.7cm high.
`
`Most passenger car mirrors are not this large vertically, and are closer to
`
`10.2cm to 11.4cm. However, the requirements of the standard are met.
`
`25
`
`Figure 4 shows mirror 12 adjusted so that the horizon 30 lies at its
`
`center. Point 24 is shown in the lower left-hand corner. Also shown is point
`
`28 in the right-hand corner. Line 32 represents the dashed yellow lane
`
`marker between the two left lanes. Line 34 represents the left edge of the left
`
`lane. Lines 32 and 34 converge at infinity on the horizon. The mirror has
`
`11
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`SMR USA
`Exhibit 1013
`Page 012
`
`

`

`WO 01/81956
`
`PCT/USOl/13283
`
`been adjusted so that point 28 is just visible, i.e. rotating the mirror farther
`
`outward would make point 28 disappear from view.
`
`As previously mentioned, a mirror constructed to just meet the
`
`5
`
`requirement in its horizontal field of view would have an excessively large
`
`blindzone. This could be remedied by providing an auxiliary blindzone(cid:173)
`
`viewing mirror of less than unit magnification with a wide field of view, located
`
`such that it does not interfere with line 34. Such an auxiliary mirror 36 is
`
`shown in Figure 5 attached to a plane main viewing mirror 40. Mirror 36 is a
`
`10
`
`spherically convex mirror having dimensions and an orientation such that its
`
`field of view encompasses the region in Figure 1 between lines 18 and 38.
`
`Mirror 36 can be made small enough so that is does not excessively encroach
`
`on the plane area of the main viewing mirror 40 above line 34. For example, if
`
`mirror 40 is 1 O cm wide, mirror 36 could easily be 4.4 X 4.4 cm square. Using
`
`15
`
`4.4 cm as the horizontal dimension for mirror 36, the radius of curvature
`
`required to encompass the blindzone can be calculated from another equation
`
`in SAE Technical Paper 950601. There it is shown that the field of view of a
`
`convex mirror is,
`
`20
`
`e -2[2
`
`-
`
`-1 w
`tan
`-
`2r
`
`-1 WCOSA+D]
`+ tan
`~
`2
`2 + 2
`SL
`ST
`
`.
`
`Eq.7
`
`All of the variables in Equation 7 are the same as Equation 1 except for r,
`
`which is the radius of curvature of the convex mirror. Angle 8 in Equation 7 is
`
`to be taken as the angle between lines 18 and 38 in Figure 1. Line 38 is seen
`
`25
`
`to extend from mirror 12 and intersect the peripheral vision line 20 in the
`
`center of the adjacent lane. The angle between lines 18 and 38 is about 25°.
`
`Using w = 4.5cm, SL= 46.0cm, Sr= 61.0cm and D = 6.4cm, r calculates out
`
`to be 29.9cm. Selection of 25° as the blindzone width is partially subjective.
`
`It involves the choice of the peripheral vision angle, the positioning of the
`
`30 mirror and an estimate of how much of the geometrically defined blindzone
`
`must be included to assure that a driver is able to see a vehicle in the
`
`12
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`SMR USA
`Exhibit 1013
`Page 013
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`

`

`WO 01/81956
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`PCT/USOI/13283
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`blindzone. In general a radius of curvature in the range of 20cm to 35cm will
`
`be satisfactory depending upon the vehicle.
`
`A key factor in the shaping and positioning of the blindzone-
`
`5
`
`viewing mirror is the required location of the center of the sphere from which
`
`the segment is taken. A vehicle in the blindzone should appear centered in
`
`the auxiliary blindzone-viewing mirror. Figures 6, 7 and 8 comprise a
`
`geometric orthographic projection showing the proper orientation of a
`
`spherically convex mirror segment 36 relative to a plane mirror 40. A radius
`
`10
`
`42 and an arc 44 of the sphere from which segment 36 is taken, must pass
`
`through the center 46 of the face of segment 36. The location of the center of
`
`the sphere must be specified so that centering of the image of a vehicle in the
`
`blindzone will occur.
`
`15
`
`As previously stated, most drivers adjust their mirrors so that if
`
`they were on a straight and level road, the horizon would be approximately
`
`centered in the mirror. Vertical centering of an image in the blindzone-viewing
`
`mirror 36 then requires that the image of the horizon pass through center 46
`
`of mirror 36. This simply requires that radius 42 lie in a plane perpendicular to
`
`20
`
`plane mirror 40, and that the plane also pass through center point 46, as
`
`shown in Figure 7.
`
`Horizontal centering of the view of the blindzone in mirror 36
`
`requires that radius 42 be located such that it passes through center 46 of
`
`25 mirror 36 and also falls along line 48 in Figure 1 which bisects the acute angle
`
`formed by lines 18 and 38. The actual position of radius line 42 in Figure 8
`
`relative to the vehicle is dependent upon how the driver has positioned the
`
`mirror relative to the vehicle. However, the position of line 42 relative to line
`
`50 in Figure 8 is constant. If the driver is instructed to position the plane
`
`30 mirror so that the side of the car is just visible, the position of line 42 is then
`
`effectively constant relative to the side of the vehicle, and the blindzone view
`
`is effectively centered about line 48 in Figure 1.
`
`13
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`SMR USA
`Exhibit 1013
`Page 014
`
`

`

`WO 01/81956
`
`PCT/USOl/13283
`
`The field of view in the plane main viewing mirror is e degrees wide
`as shown in Figure 1. If the driver so chooses, he or she could readjust the
`main viewing mirror so angle e straddles line 48. Then, the plane mirror view
`would be centered on the blindzone. Many drivers actually set their mirrors
`
`5
`
`this way to view the blindzone. Since the angle of reflection is equal to the
`
`angle of incidence, rotating the field of view outward by say 30°, would require
`
`rotating the mirror outward by 15°. Hence, to make the plane mirror look into
`
`the center of the blindzone requires that it be rotated by 1/2 of the angle
`between line 48 and line 52, where line 52 bisects angle e. Again selecting
`the blindzone width as 25°, and using a value of 15° for e, the field of view
`would have to be rotated 112 (25° + 15°l = 20°. This would require rotating the
`
`10
`
`mirror 10° to look into the center of the blindzone with the plane mirror.
`
`The same reasoning applies to the convex blindzone-viewing mirror.
`
`15
`
`If radius 42 were perpendicular to the surface of plane mirror 40, the field of
`
`view of the convex mirror would be centered about line 52 in Figure 1. But we
`
`want the spherical mirror's field of view to be centered about line 48 when the
`
`plane mirror is adjusted to just see the side of the vehicle. Therefore in Figure
`
`8, line 42 should be at an angle of 10° to line 50. The exact angle chosen will
`
`20
`
`be dependent upon the vehicle and the assumptions made for the position of
`
`line 48 in Figure 1.
`
`The criteria required to size, place and orient the less than unit
`
`magnification auxiliary blindzone-viewing mirror have now been established.
`
`25
`
`Using these criteria will provide a mirror which conforms with FMVSS 111,
`
`centers the image of a vehicle in the blindzone in the less than unit
`
`magnification mirror, and optimizes the image size for the space allocated to
`
`the less than unit magnification mirror. Mirror 36 in Figure 5 may be
`
`visualized as a spherically convex bull's-eye mirror wherein all extraneous
`
`30
`
`portions of the bull's-eye have been removed, leaving only that portion which
`
`will show a vehicle in the blindzone. When driving with a mirror so configured,
`
`a vehicle overtaking on the driver's side will be seen in the main viewing
`
`mirror when the vehicle is to the rear of the blindzone. As the vehicle
`
`14
`
`SMR USA
`Exhibit 1013
`Page 015
`
`

`

`WO 01/81956
`
`PCT/USOl/13283
`
`approaches, it appears to slide outwardly off of main viewing mirror 40 and
`
`onto blindzone-viewing mirror 36. Figure 9 shows an overtaking vehicle at
`
`various distances behind vehicle 10 of Figure 1. Figures 1 Oa, 1 Ob, 1 Oc and
`
`1 Od show the position of the image of the overtaking vehicle on mirror 12 in
`
`5
`
`Figure 9. Note that a small portion of the left rear fender of vehicle 10 is seen
`
`in the lower right-hand corner of the plane main mirror. Figure 1 Od shows the
`
`image of the overtaking vehicle at a position 11 d in Figure 9 about 12 car
`
`lengths to the rear of vehicle 10. Figure 1 Oc shows the image of the vehicle
`
`at a position 11 c about 3.5 car lengths to the rear. Figure 1 Ob shows the
`
`10
`
`image of the vehicle at position 11 b about 1.25 car length back, and it is seen
`
`mostly in the plane main viewing portion of the mirror, but partially in the
`
`auxiliary blindzone-viewing portion. Figure 1 Oa shows the image of the
`
`overtaking vehicle in position 11 a, which is entirely in the blindzone, and it is
`
`seen that the image is entirely in the blindzone-viewing mirror. Thus, the
`
`15
`
`image of the approaching vehicle moves from inside to outside across the
`
`mirror, and this is one reason why the auxiliary mirror is placed in the upper
`
`and outer quadrant of the rearview mirror. Placing it on the inner quadrant
`
`would disturb the apparent flow of the image of the overtaking vehicle as it
`
`moves across the main mirror from inside to outside.
`
`20
`
`Next, various ways of implementing the combination of the main
`
`viewing mirror a