Full Prescription Data Available

Long Eye Relief

Apparent Field of 45°

Available in Quantity Without Housing

The RKE® line of eyepieces is one of our most popular designs. Originally produced for telescope use, over time they have proven useful in a wide variety of industrial and medical applications. In addition, to help customers take advantage of the powerful current optical design software, we are pleased to forward full prescription data for these eyepieces.

Prescription information available upon request. Please complete a Request for Prescription Form.

Note: All specifications presented in the matrix below have been calculated using prescription data only. Real performance will vary according to manufacturing tolerances. Spot Size at 0.7 Field calculated for best focus weighted evenly at 0 and 0.7 fields of view.

商品名称

8mm EFL RKE Precision Eyepiece  

Effective Focal Length EFL (mm) 8.0

Back Focal Length BFL (mm) 3.83

Eye Relief (mm) 8.20

Field Stop Diameter (mm) 6.6

Apparent Field (°) 45

Distortion (%) 10 (Specified @ 0.7 Field)

Spot Size (μm) 6/7 (On-Axis/0.7 Field)

Lateral Color, 0.7 Field  0.016

Total Length, Glass Only (mm) 6.57

Total Length (mm) 37.3

Reticle Adaptable No

RoHS Exempt 

12mm EFL RKE Precision Eyepiece 

Effective Focal Length EFL (mm) 12.0

Back Focal Length BFL (mm) 5.81

Eye Relief (mm) 10.70

Field Stop Diameter (mm) 9.7

Apparent Field (°) 45

Distortion (%) 5 (Specified @ 0.7 Field)

Spot Size (μm) 4/13 (On-Axis/0.7 Field)

Lateral Color, 0.7 Field  0.016

Total Length, Glass Only (mm) 10.43

Total Length (mm) 43.7

Reticle Adaptable Yes

RoHS Exempt 

15mm EFL RKE Precision Eyepiece 

Effective Focal Length EFL (mm) 15.0

Back Focal Length BFL (mm) 7.29

Eye Relief (mm) 13.40

Field Stop Diameter (mm) 11.9

Apparent Field (°) 45

Distortion (%) 5 (Specified @ 0.7 Field)

Spot Size (μm) 4/13 (On-Axis/0.7 Field)

Lateral Color, 0.7 Field  0.016

Total Length, Glass Only (mm) 13.02

Total Length (mm) 49.4

Reticle Adaptable Yes

RoHS Exempt 

21mm EFL RKE Precision Eyepiece    

Effective Focal Length EFL (mm) 21.5

Back Focal Length BFL (mm) 11.73

Eye Relief (mm) 18.80

Field Stop Diameter (mm) 17.3

Apparent Field (°) 45

Distortion (%) 5 (Specified @ 0.7 Field)

Spot Size (μm) 3/12 (On-Axis/0.7 Field)

Lateral Color, 0.7 Field  0.014

Total Length, Glass Only (mm) 16.69

Total Length (mm) 53.5

Reticle Adaptable Yes

RoHS Exempt 

28mm EFL RKE Precision Eyepiece 

Effective Focal Length EFL (mm) 28.7

Back Focal Length BFL (mm) 15.67

Eye Relief (mm) 24.5

Field Stop Diameter (mm) 23.3

Apparent Field (°) 45

Distortion (%) 5 (Specified @ 0.7 Field)

Spot Size (μm) 3/13 (On-Axis/0.7 Field)

Lateral Color, 0.7 Field  0.018

Total Length, Glass Only (mm) 22.34

Total Length (mm) 59.0

Reticle Adaptable Yes

RoHS Exempt