Abstract:
A housing for a magnification loupe is provided having a body portion for an eyepiece lens and a nose portion for an objective lens. The body portion for the eyepiece lens includes outer circumferential threads over which the objective nose portion fits. The objective nose portion includes a pin slot defining an arc across the body of the nose. The arc is configured such that a pin may be secured through the holes in the nose piece to co-act with the threads of the eyepiece body such that radial movement is prohibited.

Description:
RELATED APPLICATION 
     This application is a continuation application of Ser. No. 09/062,936, filed Apr. 20, 1998, entitled “MAGNIFICATION VIEWER”, now U.S. Pat. No. 6,201,640, which claims priority from Provisional Application Serial No. 60/069,496, filed Dec. 15, 1997. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to magnification viewers worn by surgeons and dentists. In particular, the invention relates to an assembly for optical views or loupes which allow a user to adjust an objective lens at a predetermined distance from an eyepiece lens to vary the focal point. 
     BACKGROUND OF THE INVENTION 
     Magnification viewers, including, but not limited to, pairs of magnification loupes, are worn by dentists and surgeons for extended periods of time during clinical procedures. These viewers are worn to provide clarity of view while avoiding a hunched-over position that can result over time in debilitating neck and back strain, which can also have an adverse effect on the success of the operation. The viewers permit the clinician to operate at a greater working distance from the patient. Higher magnification viewers also reduce the clinician&#39;s exposure to aerosols. Because clinicians use magnification viewers during surgery and other procedure requiring manual precision, it is important that the viewers be light-weight, comfortable and have good clarity and wide field of vision while providing high magnification and good depth of field. 
     Surgical telescopes may be attached to a spectacle frame in one of two manners: outside-the-carrier or prescription lens (“outside-the-lens”), on an adjustment mechanism that provides for adjustment of the interpupillary distance and convergent angle variability, or through-the-lens, permanently cemented and fixed in place. Magnification viewers used by surgeons and dentists typically have a predetermined magnification. Neither the working distance nor the magnification may be changed without a tedious process of replacing either individual lens elements or the entire optical loupes themselves. Accordingly, there is a need for a simple method for changing the magnification of viewers being worn by a surgeon or dentist, as well as for altering the working distance of viewers having a particular magnification. 
     SUMMARY OF THE INVENTION 
     In accordance with one embodiment of the invention, a housing for a magnification loupe is provided having an eyepiece portion for an eyepiece lens and a nose portion for an objective lens. The body portion for the eyepiece lens includes outer circumferential threads over which the objective nose portion fits. The objective nose portion includes a pair of apertures for receiving a pin. The apertures are configured such that the pin forms a chord across the body of the nose portion and co-acts with the threads of the eyepiece body forming an axial mechanical stop to prevent the nose portion from being removed during adjustment. 
     Magnification loupes, according to the present invention, include a nose housing for an objective lens and a body housing for an eyepiece lens. The system is configured such that the magnification of the magnification loupe may be changed simply by removing the nose housing and replacing it with another. The working distance for a particular magnification level may be adjusted by threading or unthreading the nose housing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A better understanding of the present invention is obtained when the following detailed description is considered in conjunction with the following drawings in which: 
     FIGS. 1A-1C are perspective views of a magnification loupe in accordance with the present invention illustrating the connection of a pair of magnification loupes according to an embodiment of the present invention secured through the lenses of a pair of spectacles forming a magnification viewer in accordance with the present invention; 
     FIG. 2 is a perspective view of magnification loupes according to the present invention secured to an adjustable nose piece for securing to a pair of spectacles; 
     FIG. 3A is an exploded perspective view of the magnification loupes assembly for the magnification loupes of FIGS. 1 and 2; 
     FIG. 3B is a side cross-sectional view of the magnification loupe of FIG. 3A; 
     FIG. 4 is a side-elevation view of a nose housing forming a portion of the magnification viewers of FIGS. 1 and 2; 
     FIGS. 5A and 5B are side cross-sectional views and detail side cross-sectional views, respectively, of the housing of FIG. 4; 
     FIG. 6 is a top plan view of the nose housing of FIGS. 4 and 5; 
     FIG. 7 is a side elevational view of the eyepiece housing of FIGS. 1 and 2; 
     FIGS. 8A-8C are side cross-sectional views of the housing of FIG. 7, including details thereof; 
     FIG. 9 is a top plan view of the eyepiece housing of FIGS. 7 and 8; 
     FIG. 10 is a side elevational view of a spacer for the magnification loupes of FIGS. 1 and 2; 
     FIG. 11 is a side cross-sectional view of the spacer of FIG. 10; 
     FIG. 12 is a top elevational view of the spacer of FIGS. 10 and 11; 
     FIG. 13 is a side elevational view of a field stop of the magnification viewer of FIGS. 1-3; 
     FIG. 14 is a side cross-sectional view of the spacer of FIG. 13; 
     FIG. 15 is a top plan view of the spacer of FIGS. 13 and 14; 
     FIG. 16 is a side elevational view of an objective lens retainer ring of the magnification loupes of FIGS. 1-3; 
     FIG. 17 is a side cross-sectional view of the objective retainer of FIG. 16; 
     FIG. 18 is a top plan view of the objective retainer of FIGS. 16 and 17; 
     FIGS. 19A and 19B are exploded perspective views of a prism assembly for the magnification loupes of FIGS. 1-3; 
     FIGS. 20A,  20 B and  21 - 22  illustrate a prism for the prism assembly of FIGS. 19A and 19B; 
     FIGS. 23-26 illustrate the prims assembly of FIG. 19; 
     FIGS. 27-29 illustrate the roof prism of the prism assembly of FIG. 19; 
     FIGS. 30-32 illustrate the second prism of the prism assembly of FIG. 19; 
     FIG. 33 is a diagram of the optical layout of the magnification loupe of FIG. 31; and 
     FIG. 34 is an optical layout diagram of the optical loupe of FIG. 31, according to an alternate embodiment. 
    
    
     DETAILED DESCRIPTION 
     Turning now to the drawings and with particular attention to FIG. 1, a magnification viewer  10  including a pair of spectacles  100  with through-the-lens magnification loupes  106   a ,  106   b . As illustrated, the magnification loupes  106   a ,  106   b  are of the Keplerian design. The spectacles  100  include carrier lenses  102   a ,  102   b . The carrier lenses  102   a ,  102   b  may be either plano lenses or prescription lenses. The magnification loupes  106   a ,  106   b  are fixed in the carrier lenses  102   a ,  102   b  to provide stereoscopic vision. The magnification loupes  106   a ,  106   b  are set at the user&#39;s interpupillary distance converging to a desired working distance, for example, anywhere from 12 to 24 or 13 to 21 inches. As will be discussed in greater detail below, from a selected working distance, the user has the option to vary the viewing distance by rotating the objective lens housing or nose housing  108   a ,  108   b  of each magnification loupe  106   a ,  106   b  to the desired focus. As will be discussed in more detail below, one of the objective lens housings  108   a ,  108   b  and one of the eyepiece housings  110   a ,  110   b  are formed with threads, which cooperate with a pin attached to the other housing to form a threaded coupling. The eyepiece housings,  110   a ,  110   b , in turn, are secured to the carrier lenses  102   a ,  102   b  by various techniques, including a friction fit or with an adhesive, such as epoxy. Alternatively, the eyepiece housings  110   a ,  110   b  may be secured to the carrier lenses  102   a ,  102   b  by way of known threading on the outside of the eyepiece housings  110   a ,  110   b  matching threading on the carrier lenses  102   a ,  102   b.    
     As will be discussed in greater detail below, magnifications of 3.3×, 3.8×, 4.3× and 4.8× are possible, according to one embodiment of the invention to provide a wide range of selection. For each magnification, working distances of about 12″, 16″ and 24″ may be provided. The carrier lenses  102   a ,  102   b  normally enable a user to focus comfortably at 500 mm, about −2D, a typical reading distance. The magnification loupes  106   a ,  106   b , as will be discussed in greater detail below, further include a prism system (FIGS.  19 - 32 ). Each magnification loupe uses an identical prism and eyepiece lens system. For different magnifications, only the objective lenses are changed. The user may create depth of field by adjusting the focal distance of each eye depending upon the operation being performed. the focuses of each of the magnification loupes  106   a ,  106   b  may be changed independently. The aperture for the objective lens has been reduced in size to provide an increase in depth of field at high magnifications while still providing substantial light. 
     Turning now to FIG. 2, an alternative configuration of the magnification loupes  106   a ,  106   b  of FIG. 1 is illustrated. It is noted that for the lens system  20  of FIGS. 2, the optical configurations of the magnification loupes  206   a ,  206   b  are different from the through-the-lens configuration of FIG. 1, but the barrels or housings are similar in that only the objective lens need be changed to provide different magnifications. The prism and eyepiece remain the same. The optical system  20  of FIG. 2 includes a pair of spectacles  200  including a pair of carrier lenses  202   a ,  202   b  and a binocular magnification viewer  25 , including a pair of magnification loupes  206   a ,  206   b . As discussed in U.S. Pat. No. 5,667,291, the binocular magnification viewer  25  may be attached to the spectacles  200  by a pivot member  250 . Alternatively, the magnification loupes  206   a ,  206   b , may be mounted close to the spectacle lenses, for example, about 0.5mm from the carrier lenses  202   a ,  202   b . The pivot member  250 , in turn, is attached to a bridge  258  which includes a bridge adjustment knob  252  for adjusting a pair of extension of arms  254 ,  256  to enable the interpupillary distances of the loupes  206   a ,  206   b  to be adjusted. The interpupillary distance of the magnification loupes  206   a ,  206   b  may further be adjusted by knobs  260   a ,  260   b .The binocular magnification viewer  25  may be secured to the spectacles  200  by way of a clip, screws, glue or other known methods. 
     Mechanical Characteristics 
     Turning now to FIG. 3A, an exploded perspective view of the magnification loupes  106  in accordance with the present invention are shown. For the purposes of this discussion, only one of the magnification loupes  106  and its components shall be discussed. It is understood, however, that all descriptions are equally applicable to loupe  106   b  and its components. The magnification loupes  106   a  include a nose or objective housing  108   a  and a body or eyepiece housing  110   a . As illustrated, the objective housing  108   a  includes a frusto-conical front portion  350  and a generally cylindrical rear portion  352 . It is noted that the housing  108   a  may be of different shapes; thus, FIG. 3 is exemplary only. The objective housing  108   a  includes a pair of apertures  304 . The apertures  304  are configured to receive a pin  302  such that the pin  302  defines a chord across the cylindrical rear portion  352  of the objective housing  108   a . More particularly with reference to FIG. 3B, the objective housing  108   a  includes an interior surface  308  which engages an exterior surface  307  of the eyepiece housing  110   a . Spiral threads  306  are formed into the surface of the eyepiece housing  110   a . The apertures  304  are located in the objective housing  108   a  so that the pin  302  engage the spirals or threads  306 . The pin  302  enables a threaded coupling between the two housings  106   a  and  108   a  even through only one housing  110   a  is formed with threads. The threaded coupling between the housings  106   a  and  108   a  permits the working distance of the loupes  106   a  and  106   b  to be adjusted by rotating the objective housing  108   a  relative to the eyepiece housing  110   a , which in turn, varies the distance between the eyepiece and objective lenses which varies the working distance between the loupes  106   a  and  106   b.    
     Another important aspect of the invention is that the configuration allows the magnification of the loupes  106   a  and  106   b  to be rather easily changed. More particularly, the pin  302  may be removably mounted relative to the objective housing  108   a  or fixedly mounted with the use of epoxy. Depending on the embodiment, the magnification of the loupe can be rather easily changed at the factory or by the user, or both. In particular, as will be discussed in more detail below, the magnification of the loupe  106   a  is changed simply by changing the objective lens in the loupe  106   a . The objective lenses are easily changed by removing the pin  302  which enables the objective housing  108   a  to be removed so that the objective lens  312  can be removed and replaced. As will be discussed in more detail below, an important aspect of the invention relates to the ability to vary the magnification of the loupe  106   a.    
     As best illustrated in FIGS. 3A and 3B, the objective lens  312  is configured to rest within a first interior portion  360  of the objective housing  108   a . The interior portion  360  includes a circumferential slot  311  for seating an O-ring  310  therein. The objective lens  312  rests against the O-ring  310  and is engaged in place by a threaded retainer ring  314 . The retainer ring  314  includes external threads to engage corresponding threads on the interior portion  360  of the objective housing  108   a.    
     Additional details concerning the objective housing  108   a  are illustrated in FIGS. 4-6. For example, the exterior of the objective housing  108   a  may include a knurled portion  109  for easy engagement of the objective housing  108   a  to the eyepiece housing  110   a.    
     The eyepiece housing  110   a , illustrated in greater detail in FIGS. 7-9, includes a forward engagement portion  307  and a rear cylindrical portion  309 . As discussed above, the forward engagement portion  307  includes threads  306  for engagement with the pin  302 . It is noted that according to one embodiment of the invention, the threads  306  are circular threads rather than notched or V-shaped threads so as to more effectively engage the pin  302 . The eyepiece housing  110   a  includes internal threads  340  positioned where the engagement housing  307  meets the rear cylindrical portion  309 . The threads  340  are configured to engage the threads  341  of the field stop  318  (FIGS. 3A,  3 B). The rear cylindrical portion  309  of the eyepiece housing  110   a  further includes a circumferential platform  344 , configured to receive a lens  332 , for example, a prescription lens. The lens  332  is held in place against the platform  344  in contact with a prescription lens O-ring  340  and a retainer ring  334 , which has external threads that engage the internal threads  342  of the eyepiece housing  110   a . In the embodiment illustrated, the rear cylindrical portion  309  of the housing  110   a  is configured to be fastened to the carrier lens  102   a  by way of a suitable adhesive, such as epoxy. In an alternative embodiment, however, the rear cylindrical portion  309  may be provided with threads to engage similar threads in the carrier lens. 
     The forward engagement portion  307  of the eyepiece housing  110   a  is further configured to receive a prism assembly  316  (FIGS. 19A,  19 B). The prism assembly  316  includes a prism holder  317  including a pair of arms  319   a ,  319   b , a base portion  321 , and is adapted to fit within the housing  110   a . The forward portions of the arms  319   a ,  319   b  include circular cutout portions  323   a ,  323   b , respectively, to engage a holder ring  402 . The holder ring  402  is configured, when attached in place (such as by an adhesive), to secure the prism elements  404 ,  406 ,  408 . According to one embodiment, the prism elements (FIGS. 20 a - 22 ) form a roof-pechan prism separated by a spacer  408 . The spacer  408  is formed, for example, of a blackened ridge metal with a six millimeter diameter hole centered on the optical axis. The prism surfaces on opposite sides of the spacer are generally parallel. The individual elements of the roof pechan prism  404 ,  406  are illustrated in FIGS. 23-27 and  28 - 30 , respectively. The prism elements are formed from Schott BAK 4  or LAK 10  glass. 
     Turning back to FIGS. 3A-3B, the base of the prism assembly  316  is configured to rest against a rear wall  351  of the forward engagement portion  307  at approximately the position where it engages the rear cylindrical portion  309 . A field stop  318  (FIGS. 13-15) having external threads  341  engages the corresponding internal threads  340  of the housing  110   a . The field stop  318 further includes internal grooves  343 . The rear cylindrical portion  309  of the housing  110  further houses the eyepiece lens elements. As shown, the eyepiece lens includes elements  320  and  324 , separated by a spacer  322 . The spacer  322  is illustrated in FIGS. 10-12 and may include internal concentric grooves  329  which form a light baffle. Finally, the eyepiece lens  324  rests against the platform  344 . 
     The exterior of the engagement housing  307  includes a pair of concentric circumferential grooves  325 ,  327  configured to receive the O-rings  326 ,  328 , respectively. The O-rings  326 ,  328  additionally function to self-center the objective housing  108   a  and hence, the objective lens  312  relative to the eyepiece housing  110   a.    
     While the configuration described and shown with regard to FIGS. 3A-3B relates to a through-the-lens viewer, a similar configuration may be used in the outside-the-lens system shown in FIG.  2 . Such a system may be used without a prescription lens and, as will be described in greater detail below, a different eyepiece system. 
     Optical Characteristics 
     Turning now to FIG. 33, a diagram illustrating the optical layout of the magnification loupe  106   a  of FIGS. 1 and 3A,  3 B is shown. The magnification loupe  106   a  as illustrated in FIG. 33 includes a two-element objective lens including elements I-II and including a three-element eyepiece including elements III-V. R 1 , R 2  etc., represent the radii of respective refractive surfaces; S 1 -S 5  represent the thickness of the air spaces; and T 1 , T 2 , etc., represent the thicknesses of the lens elements. As discussed above, according to one embodiment of the invention, magnifications of 3.3×, 3.8×, 4.3× and 4.8× are provided. All magnifications use the same prism and eyepiece lens system. As shown in FIGS. 28 and 32, the prior angle ∝ may be used in the range 45°-49°, preferably 48° to increase the optical performance of the device while the prism angle B (FIG. 32) may be selected to be 24°. Thus, a common eyepiece housing  110   a  and optical elements included therein may be used for all of the magnifications. As discussed above, only the objective lens needs to be changed in order to alter the magnification. 
     The user may create a depth of field by adjusting the focal distance of each eye differently depending on the operation being performed. For example, a heart surgeon may wish to view the entire depth of the heart at high magnification previously unattainable in conventional magnification systems where depth of field is limited. This can be accomplished by adjusting the focus of the left eye one-inch beyond the right. When both eyes are then opened, the heart can be viewed in its entirety. However, a dentist may only require the depth of the coronal portion of the tooth to be in focus and thus would only separate the focus by a millimeter or two. Alternatively, both magnification loupes can be precisely focused at the same distance for procedures requiring the highest resolution. The following exemplary fields of view may be provided: 
     
       
         93 m@ 3.3×@16 ″WD   
       
     
     
       
         82 m@ 3.8×@16 ″WD   
       
     
     
       
         72 m@ 4.3×@16 ″WD   
       
     
     
       
         65 m@ 4.8×@16 ″WD   
       
     
     Exemplary construction data for a magnification loupe built according to the embodiment shown in FIGS. 1-3 are given in Tables I-XII. The radii, thickness, and separation dimensions are given in millimeters. Roman numerals identify the lens elements in their respective order from the objective side to the eyepoint side; n d  represents the refractive index of each element; v d  is the abbe dispersion number; R 1 , R 1 , etc., represent the radii of the respective refractive surfaces in order from the objective side to the eyepoint side; T 1 , T 2 , etc., represent the thicknesses of the lens elements from the objective side to the eyepoint side; S 1 , S 2 , etc., represent the thicknesses of air spaces respectively from the objective side to the eyepoint side measured along the optical centerline. Again, it is noted that the prism/objective distance can differ by about 2.5 mm if BAK 4  glass is used, rather than LAK 10 , as in the tables. 
     FIG. 34 illustrates an embodiment of the present invention having long eye relief characteristics. Again, the system shown in FIG. 34 employs the same prism and eyepieces, but separate objective doublets for each level of magnification. The objective doublets and the prism, however, are the same as for the through-the-lens embodiment shown in FIG.  33 . Additionally, only the eyepiece lens is changed from the through-the-lens configuration. As compared the embodiment of FIG. 33 eye relief (the distance to exit pupil) has been improved from about 17.8 mm to about 22.8 mm. 
     In particular, the viewer according to FIG. 34 includes the two-element or doublet objective including elements I-II and a four-element eyepiece lens including elements III-VI. R 1 , R 2 , etc., again represent the radii of respective refractive surfaces; S 1 , S 2 , etc., represent the thicknesses of the air spaces; and T 1 , T 2 , etc., represent the thicknesses of the lens elements. 
     Exemplary construction data for loupes according to the embodiment of FIG. 34 are given in Tables XIII-XXIV. 
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE I 
               
             
             
               
                   
               
               
                 3.3 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 6.96 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE II 
               
             
             
               
                   
               
               
                 3.3 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 5.01 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE III 
               
             
             
               
                   
               
               
                 3.3 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 3.63 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE IV 
               
             
             
               
                   
               
               
                 3.8 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.04 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 14.61 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 14.61 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 12.38 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE V 
               
             
             
               
                   
               
               
                 3.8 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.04 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 14.61 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 14.61 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 9.92 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE VI 
               
             
             
               
                   
               
               
                 3.8 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.04 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 14.61 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 14.61 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 8.02 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE VII 
               
             
             
               
                   
               
               
                 4.3 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 50.15 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 16.00 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 16.00 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 47.79 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 18.07 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE VIII 
               
             
             
               
                   
               
               
                 4.3 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 50.15 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 16.00 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 16.00 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 47.79 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 15.56 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE IX 
               
             
             
               
                   
               
               
                 4.3 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 50.15 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 16.00 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 16.00 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 47.79 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 13.13 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE X 
               
             
             
               
                   
               
               
                 4.8 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 61.12 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 16.98 
                 1.5 
                 13.4 
               
               
                   
                 SFL6 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 25.16 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XI 
               
             
             
               
                   
               
               
                 4.8 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 61.12 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 16.98 
                 1.5 
                 13.4 
               
               
                   
                 SFL6 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 21.23 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XII 
               
             
             
               
                   
               
               
                 4.8 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 νd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep.  
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 61.12 
                 4.0 
                 13.4 
                   
               
               
                   
                 BAH 27 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 16.98 
                 1.5 
                 13.4 
               
               
                   
                 SFL6 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 18.22 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 7.04 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.05 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 17.86 
               
               
                 III 
                 Ohara 
                 1.8052 
                 25.4 
                 R 3  = 44.00 
                 2.0 
                 15.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 4  = 13.00 
               
               
                 IV 
                 Ohara 
                 1.4875 
                 70.2 
                 R 5  = 13.00 
                 6.5 
                 15.4 
               
               
                   
                 FSL5 
                   
                   
                 R 6  = 13.00 
               
               
                 V 
                 Ohara 
                 1.6700 
                 47.3 
                 R 7  = 15.59 
                 3.0 
                 15.4 
               
               
                   
                 BAH10 
                   
                   
                 R 8  = 94.04 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XIII 
               
             
             
               
                   
               
               
                 3.3 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 6.96 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XIV 
               
             
             
               
                   
               
               
                 3.3 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 5.1 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XV 
               
             
             
               
                   
               
               
                 3.3 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 3.63 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XVI 
               
             
             
               
                   
               
               
                 3.8 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 12.38 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XVII 
               
             
             
               
                   
               
               
                 3.8 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 9.92 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XVIII 
               
             
             
               
                   
               
               
                 3.8 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 8.02 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XIX 
               
             
             
               
                   
               
               
                 4.3 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 18.7 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XX 
               
             
             
               
                   
               
               
                 4.3 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 15.56 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XXI 
               
             
             
               
                   
               
               
                 4.3 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 13.13 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XXII 
               
             
             
               
                   
               
               
                 4.8 × 
               
               
                 (12″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 25.16 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XXIII 
               
             
             
               
                   
               
               
                 4.8 × 
               
               
                 (16″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 21.23 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XXIV 
               
             
             
               
                   
               
               
                 4.8 × 
               
               
                 (24″ WD) 
               
             
          
           
               
                 Element 
                 Glass 
                 nd 
                 vd 
                 Radius 
                 Thickness 
                 Diameter 
                 Sep. 
               
               
                   
               
             
          
           
               
                 I 
                 Ohara 
                 1.7015 
                 41.2 
                 R 1  = 42.19 
                 3.5 
                 13.4 
                   
               
               
                   
                 BAH 27 
                   
                   
                 R 2  = 12.45 
               
               
                 II 
                 Ohara 
                 1.8052 
                 25.4 
                 R 2  = 12.45 
                 1.5 
                 13.4 
               
               
                   
                 PBH6W 
                   
                   
                 R 3  = 36.00 
               
               
                 Prism A 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 1  = 18.22 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 2  = 3.41 
               
               
                   
                   
                   
                   
                   
                   
                   
                 S 3  = 2.33 
               
               
                 Prism B 
                 BAK4 
                 1.5688 
                 56.13 
                   
                   
                   
                 S 4  = 0.5 
               
               
                   
                 LAK10 
                 1.7200 
                 50.41 
                   
                   
                   
                 S 5  = 22.8 
               
               
                 III 
                 Ohara 
                 1.5410 
                 47.2 
                 R 4  = PLANO 
                 3.0 
                 12.0 
               
               
                   
                 S-TIL2 
                   
                   
                 R 5  = 12.61 
               
               
                 IV 
                 Ohara 
                 1.923 
                 21.3 
                 R 5  = 12.61 
                 1.5 
                 15.4 
               
               
                   
                 PBH71 
                   
                   
                 R 6  = 12.61 
               
               
                 V 
                 SCHOTT 
                 1.5168 
                 64.2 
                 R 7  = 10.06 
                 7.1 
                 15.4 
               
               
                   
                 BK7 
                   
                   
                 R 6  = 12.61 
               
               
                 VI 
                 SCHOTT 
                 1.744 
                 44.8 
                 R 8  = 25.11 
                 4.7 
                 17.5 
               
               
                   
                 S-LAM2 
                   
                   
                 R 9  = 25.11 
               
               
                   
               
             
          
         
       
     
     The invention described in the above detailed description is not intended to be limited to the specific form set forth herein, but, on the contrary, is intended to cover such alternative, modifications and equivalents as can reasonably be included within the spirit and scope of the appended claims.