VUV CaF2 Bi-CX/Bi-CC Lenses

 

Vacuum Ultraviolet (VUV-UV) Bi-Convex & Bi-Concave Spherical Lenses are available in select VUV Grade Calcium Fluoride (CaF2) for a wide range of VUV-UV optical applications including VUV-UV instrumentation or VUV-UV lasers.  VUV-UV CaF2 Bi-Convex & Bi-Concave Spherical Lenses have two spherical surfaces with the same Radius of Curvature either curved outward (Bi-Convex) or curved inward (Bi-Concave).  

VUV CaF2 Bi-Convex Spherical Lenses have positive Effective Focal Lengths (EFL) and are popular for many finite imaging applications. Both spherical convex surfaces are designed to minimize aberrations in lens applications where the object and image distances are equal or nearly equal. As a example, VUV CaF2 Bi-Convex Spherical Lenses are the best choice for minimizing aberrations if the conjugate ratio (object distance : image distance) is between 5:1 and 1:5. Outside this range, VUV CaF2 or MgF2 Plano-Convex Spherical Lenses are typically used.

VUV CaF2 Bi-Concave Spherical Lenses have negative Effective Focal Lengths (EFL) and cause incident VUV-UV light to diverge, which is useful in a wide range of VUV-UV applications.  VUV CaF2 Bi-Concave Spherical Lenses are typically used to increase the divergance of a converging beam.  In VUV-UV optical system applications, VUV CaF2 Bi-Concave Spherical Lenses are often used in pairs to increase the effective focal length of a converging lens. It is also common to use both Bi-Convex and Bi-Concave lenses in the same application so that the aberrations introduced by the positive and negative focal length lenses approximately cancel.

As VUV CaF2 Bi-Concave Spherical Lenses cause incident VUV-UV light to diverge, it is usually preferrable to choose a VUV CaF2 Bi-Concave Lens if the absolute conjugate ratio (object distance divided by image distance) is close to 1.  When deciding between a VUV CaF2 Bi-Concave and VUV CaF2 Plano-Concave Lens, typically a VUV CaF2 Plano-Concave Lens is used when the desired absolute magnification is either less than 0.2 or greater than 5. 

Also see our VUV Grade CaF2 Plano-Concave Spherical Lenses , VUV Grade MgF2 & CaF2 Plano-Convex Spherical Lenses & VUV-UV CaF2 Positive & Negative Meniscus Lenses

 

VUV Grade Calcium Fluoride (CaF2): CaF2 exhibits good transmission properties from ~ 145nm Vacuum UV (VUV) to ~ 8.0um in the Infrared.  CaF2 is a relatively soft crystalline material and care should be taken as CaF2 is sensitive to mechanical and thermal shock.  CaF2 is a cubic single crystal optical material.
 

More information can be found on our Material Properties Page.   For more information about Spherical Lenses, refer to our Optics Tutorial page
                               

SPECIFICATIONS

Material: VUV Grade CaF2
Effective Focal Length (EFL) Tol.: ± 2% 
Radius of Curvature (ROC) Tol.: within ±1%     
Diameter (Dia = Ø) Tolerance: ±0.25mm
Thickness Tolerance: ±0.25mm  
Surface Figure: ~L/2 @ 633nm nominal
Surface Finish:  40-20 both surfaces
Clear Aperture: central 85%
Centration: < 3 arc minutes 
Chamfer: ~ 0.30mm @45 deg.

(All dimensions in mm)

 

        

 

 
 

DIA  Ø (mm)

RADII (R1 & R2)

EFL @ 157nm

EFL @ 193nm

EFL @ 248nm


BACK FOCAL LENGTH

 (BFL @ 193nm)


 CENTER THICKNESS

    (CT) 

DESCRIPTION

 MATERIAL

  PRICE  


 PRODUCT #  ORDER

12.7mm

12.1mm CX         

11.8mm

13.1mm

13.9mm

11.1mm

5.6mm

VUV-UV CaF2 Bi-Convex Lens

VUV CaF2

$250.00

CF1212BICX

12.7mm 16.6mm CX 15.6mm 17.3mm 18.6mm 15.8mm 4.5mm

VUV-UV CaF2 Bi-Convex Lens

VUV CaF2

$250.00 CF1216BICX
12.7mm 34.2mm CX 31.1mm 34.6mm 37.1mm 33.6mm 3.2mm

VUV-UV CaF2 Bi-Convex Lens

VUV CaF2

$250.00 CF1234BICX
25.4mm 20.2mm CX 20.0mm 22.2mm 23.7mm 18.1mm 11.0mm

VUV-UV CaF2 Bi-Convex Lens

VUV CaF2

$275.00 CF2520BICX
25.4mm 42.5mm CX 39.0mm 43.4mm 46.4mm 41.4mm 5.9mm

VUV-UV CaF2 Bi-Convex Lens

VUV CaF2

$275.00 CF2542BICX

25.4mm

64.4mm CX

58.4mm

65.0mm 69.6mm 63.5mm

4.5mm

VUV-UV CaF2 Bi-Convex Lens

VUV CaF2

$275.00

CF2564BICX

25.4mm 86.2mm CX 77.8mm 86.6mm 92.7mm 85.3mm 3.9mm

VUV-UV CaF2 Bi-Convex Lens

VUV CaF2

$275.00 CF2586BICX

25.4mm

173.1mm CX

155.4mm 173.1mm 185.4mm 172.2mm

2.9mm

VUV-UV CaF2 Bi-Convex Lens 

VUV CaF2

$275.00

CF25173BICX

12.7mm -13.4mm CC -11.6mm -13.0mm -13.9mm -11.6mm 2.5mm

VUV-UV CaF2 Bi-Concave Lens

VUV CaF2

$230.00 CF1213BICC

12.7mm

-22.1mm CC

-19.3mm

-21.5mm -23.1mm -22.5mm

3.0mm

VUV-UV CaF2 Bi-Concave Lens 

VUV CaF2

$230.00

CF1222BICC

25.4mm -26.4mm CC -23.2mm -25.9mm -27.8mm -26.7mm

5.7mm

VUV-UV CaF2 Bi-Concave Lens

VUV CaF2

$275.00 CF2526BICC

25.4mm

-43.8mm CC

-38.7mm

-43.2mm -46.3mm -44.2mm

4.9mm

VUV-UV CaF2 Bi-Concave Lens

VUV CaF2

$275.00

CF2543BICC

 

                               

 

                                                                                  CaF2 Refractive Index 

Wavelength, nm 157 193 248 308 350
Refractive Index (n) 1.559 1.501 1.468 1.453 1.445

                                                

                                                   
              eSource Optics / PMB 126 / 1225 Providence Rd. / Whitinsville, MA 01588

 VUV-UV Optical Filters & Mirrors/Windows/Lenses/Hardwood Optics Cases & Boxes