LB Objectives for Olympus BH2 Microscopes
Click here to see the detailed specifications of the LB objectives.
LB Objective Lenses
Objective lenses in the Olympus LB family were made in several basic optical designs, which determined their overall degree of aberration (spherical and chromatic) compensation. These basic designs were: 1) achromatic, 2) fluorite, and 3) apochromatic. The lowest performing of these three types were the achromats, while the highest performing were the apochromats. The fluorites fell in between achromatic and apochromatic performance (this is why fluorites have often been referred to as “semi-apochromats”).
Separate from the three basic optical design types listed above, LB objectives were made with various degrees of field coverage and flatness. These include a collection of low-cost educational objectives (marked “E” on the barrel), a collection of standard non-plan objectives (referred to as D objectives in Olympus literature, but marked “A” on the barrel), a collection of plan objectives (marked “DPlan” on the barrel), and a collection of super-wide plan objectives (marked “SPlan” on the barrel). The E educational objectives were always achromats of non-plan design with a modest field number of 18. The D (A) objectives were primarily achromats, but some apochromats were also made, and were non-plan with a standard field number of 20. The DPlan objectives were made in both achromats and apochromats, and were fully plan with a standard field number of 20. The SPlan objectives were also both achromats and apochromats, and were fully plan up to a super-wide field number of 26.5.
LB objectives were made to support various optical modes. E educational achromats were made in brightfield versions only. D (A) achromats were made for brightfield, darkfield, phase contrast (PL, PLL, NH, NM, and relief phase) and low-strain polarizing applications. DPlan achromats were made for brightfield, darkfield, and low-strain polarizing applications. SPlan achromats were made for brightfield, Nomarski DIC, and phase contrast (PL, NH, and relief phase) applications. Low-fluorescing D apochromats were made for brightfield, darkfield, Nomarski DIC, phase contrast (PL), and UV fluorescence applications. Low-fluorescing DPlan apochromats were made for brightfield, Nomarski DIC, phase contrast (PL), and UV fluorescence applications. SPlan apochromats were made for brightfield and phase contrast (PL) applications. Low-fluorescence fluorites were made for brightfield, darkfield, phase contrast (PL), and UV fluorescence applications. Additionally, LB objectives were made to provide long working distances (LWD) and ultra-long work distances (ULWD) for inverted microscope applications. LWD and ULWD achromats were made to support phase contrast (PL and relief phase) and Nomarski DIC applications.
LB objectives were commonly available for dry (i.e., non-immersion) imaging, as well as for oil-immersion imaging. The dry objectives were suitable for lower numerical aperture requirements, whereas oil-immersion was required when numerical apertures greater than 0.9 or so were needed. In addition to the common oil-immersion objectives, Olympus also made LB objectives to meet specific industry and research requirements, such as objectives made for water immersion and silicone immersion. LB objectives were also available for viewing without a cover slip. Many of the high numerical aperture SPlan, UVFL, or D Apo objectives, as well as many LWD and ULWD objectives, included a correction collar to accommodate non-standard coverslip thicknesses. Additionally, some of the high numerical aperture A (D), DPlan, UVFL, and D Apo objectives included an internal iris diaphragm to reduce the NA for darkfield imaging.
LB Objective Types
EDUCATIONAL ACHROMATS: Educational D achromats (marked as “EA”) were made with a field number of 18, to match the CWHK educational eyepieces. These were supplied with the CH2 microscopes, but can be used on the BH2. The EA achromats were available in the following versions:
- 4x, 10x, 40x, and 100x (oil).
STANDARD ACHROMATS: Standard D achromats (marked as “A”) were made with a field number of 20, to match the WHK and WK BH2 eyepieces. The D achromats were non-plan objectives, which were available in the following versions:
- 4x, 10x, 20x, 40x, 60x, 100x (oil), and 100x (oil) with iris.
- 10x, 20x, 40x, and 100x (oil) in PL, PLL, NH, and NM for phase contrast microscopy.
- 4x, 10x, 20x, 40x, and 100x (oil) low-strain (marked as “PO”) for polarized microscopy.
PLAN ACHROMATS: DPlan achromats (marked as “DPlan”) were made with a field number of 20, to match the WHK and WK BH2 eyepieces. The DPlan achromats are planar objectives, which were available in the following versions:
- 4x, 10x, 20x, 40x, 50x (oil), and 100x (oil) with iris.
SUPER-WIDE PLAN ACHROMATS: SPlan achromats (marked as “SPlan”) were made with a field number of 26.5, to match the SWHK BH2 eyepieces. The SPlan achromats were planar objectives, which were available in the following versions:
- 4x, 10x, 20x, 40x, 100x, and 100x (oil).
- 4x, 10x, 20x, 40x, and 100x (oil) PL and NH for phase contrast microscopy.
- 40x NC and 100x (dry) NC versions for use without a coverslip.
SUPER-WIDE FLUORITES: SPlan fluorite objectives (marked as “SPlan FL”) were made with a field number of 26.5, to match the SWHK BH2 eyepieces. The SPlan fluorite were low-power planar objectives, which were available in the following versions:
- 1x and 2x.
STANDARD APOCHROMATS: D APO apochromats were made with a field number of 20, to match the WHK and WK BH2 eyepieces. The D APO apochromats were available in the following versions:
- 20x UV, 40x (oil) UV, and 100x (oil) UV for reflected light fluorescence microscopy.
- 40x (oil) UV and 100x (oil) UV PL for reflected phase contrast fluorescence microscopy.
PLAN APOCHROMATS: DPlan apochromats (marked as “DPlan APO”) were made with a field number of 20, to match the WHK and WK BH2 eyepieces. DPlan apochromats were available in the following versions:
- 60x (dry)
- 10x UV, 20x UV, 20X (oil) UV, 40x UV, 40x (oil) UV, and 100x (oil) UV for reflected fluorescence microscopy.
- 10x UV, 20x UV, 40x (oil) UV, and 100x (oil) UV PL for reflected phase contrast fluorescence microscopy.
SUPER-WIDE PLAN APOCHROMATS: SPlan apochromats (marked as “SPlan APO”) were made with a field number of 26.5, to match the SWHK bh2 eyepieces. SPlan apochromats were planar objectives, which were available in the following versions:
- 4x, 10x, 20x, m40x, 60x (oil), and 100x (oil).
- 60x and 100x (oil) NC for use without a coverslip.
LONG-WORKING DISTANCE OBJECTIVES: TBD
ULTRA-LONG WORKING DISTANCE OBJECTIVES: TBD
The objectives listed above are the standard objectives that were commonly advertised and sold. There are more objectives in the LB series than those listed here, since a great many specialty objectives were made for specific applications. Refer to the link at the top of this page for a complete spreadsheet of all LB objective types known to the Empire of Dirt Workshop.