Objective Lens Specification Table. R indicates Retractable Lens

Infinity Objectives​​

MagnificationNumerical Aperture (mm)Field of View with 10X Eye PIece (mm)Working Distance Bright Field (mm)Working Distance Phase Contrast 
(mm)

Planachromatic

4X

0.13

5.5

12.31

NA

Planachromatic

10X

0.3

2.2

4

4

Planachromatic (optional)

20X 

0.45

1.1

1.24

1.24

Planachromatic

40X R

0.7

0.55

0.29

0.29

Planachromatic (optional)

50X (oil) R

0.9

0.44

0.12

NA

Planachromatic (optional)

60X R

0.8

0.37

0.04

0.04

Planachromatic

100X (oil) R

1.25

0.22

0.09

0.09

Illumination Matters

BK Series standard Halogen bulbs produce better intensity and color reproduction compared to LED, but LED is available and lasts much longer. Tailor light potency with aperture diaphragm, color coded to match objective's color band, ensuring optimal contrast for each magnification. A quick check on centering the light is easily accomplished with a field diaphragm. It doesn't get any easier to change the light bulb, thanks to a handy light drawer on the frame.

The Stage

One of BK Series' hardest working parts, comes with amenities: rounded corners for comfort; locking function (selectable) maintains focus even if stage is bumped, and quickly finds focus without hitting objective; a hard ceramic coating for longevity and a durable slide holder with two slide capacity.

What makes it comfortable?

Microscope controls fit naturally, apparent when you sit in front of this instrument. Height adjustable focus knobs facilitate relaxed posture

Light intensity control is handily accessible, located above right focus knob.

A 30° angled viewing tube with adjustable diopters to allow for corrected vision; rubber eye guards and high eye point eyepieces are standard.

What makes BK Series Durable?

    A compact footprint that commands little bench space is all cast metal, so it's heavy, durable, and with a wide rear Y shape base it avoids tip overs, protects the focus mechanism from bumps and improves vibration resistance.

     A 5 Year Warranty includes parts and labor, and the Reliability comes with Jenco stocking replacement parts for now and the next 10 Years at least, as our 15 year history can prove.

     All glass and metal components leave no plastic gears to break or lens covers to scratch; the Integrated Handle for transporting ease,

   Anti-germ, anti-microbial, anti-fungal treatment minimizes chance to transfer bacteria or accumulate mold harmful to optics and frame

Does it need to be Versatile?

This instrument can change when your specimen needs change. Simply add a module for one of these techniques:

  • Fluorescence for AFB, Acid-Fast Bacillus or TB
  • Phase Contrast for specimens not naturally colored or stained
  • Polarization for Crystal identification in Urine or elsewhere
  • Digital Imaging, facilitated via a trinocular port

Jenco keeps module selections simple, making complete kits available as one part number,like JC-EPI for fluorescence, or BK-PHP for phase, and more, all ready to install on the primary frame.

How do you obtain Superb Resolution?

​​​​Infinity corrected Planachromatic optics provide outstanding flatness, clarity, contrast and color correctness for research grade performance, revealing intricate specimen structures. Planachromatic is an optical quality level that corrects for color and spherical aberrations, producing a flat field of view from the edge, eliminating time consuming re-focusing.

The Infinity design adds versatility, allowing for a modular or kit system to be added at any time while delivering grand views. And BK Series exposes more specimen in the field of view with 22mm wide 10X eyepieces.


Additional objectives, like a 50Xoil, are readily available and an optional 5 hole turret makes installation and use convenient.

BK Series Optics Deliver Brilliant Images

See what you need to, experience Comfort in viewing, and Save Money with a Dependable Brand Jenco International, Inc.


More than superb resolution at an Affordable price, BK Series offer:

  • Durability with Reliable support
  • Versatility to respond now and grow with your needs
  • ​Comfort from unique design elements
  • Speed - find and examine your specimen quickly

Jenco International, Inc.

Models Available

Standard Configuration

Bright Field

BF with Polarization for Clinical Use

Phase Contrast

Fluorescence

Polarization

Binocular

BK -211

BK -2PL

BK -221

BK -2EF

BKPL-211

Trinocular

camera attachment

BK -311

BK -3PL

BK -321

BK -3EF

PL-311

Modules/Kits for add on

NA

NA

BK -PH

BK -EPI

JC -PL