Invitrogen™ EVOS™ Objective Starter Kit for Fluorescence/Brightfield/Phase Contrast

Additional characteristics of this EVOS objective bundle:

EVOS 4X Objective, fluorite (Cat. No. AMEP4980)

• Magnification: 4X
• Numerical aperture: 0.13
• Working distance: 10.58 mm

EVOS 10X Objective, fluorite (Cat. No. AMEP4981)

• Magnification: 10X
• Numerical aperture: 0.30
• Working distance: 7.13 mm

EVOS 20X Objective, fluorite (Cat. No. AMEP4982)

• Magnification: 20X
• Numerical aperture: 0.45
• Working distance: 6.12 mm

Image quality

Microscope objectives may be the most important components of an optical microscope because they are responsible for primary image formation. Image quality is crucial to experimental success and a requirement for publication; EVOS objectives afford that quality across the visible spectrum to near infrared light. This performance results from years of lens manufacture perfection. EVOS objectives have the same or better numerical apertures as any other manufacturer's in the same class, and the broad selection means you have choices for your imaging requirements.

Objective classes

Achromat objectives are excellent for general applications, with standard correction of color and focus.

Fluorite objectives deliver excellent resolution and are made with higher numerical apertures than achromat objectives, resulting in brighter fluorescence signal and higher contrast imaging. The higher optical quality greatly reduces optical aberrations, and corrections for color and focus are at higher levels than achromat objectives. Fluorite objectives are well-suited for fluorescence and demanding transmitted light applications, where the higher contrast make them well-suited for color imaging.

Apochromat objectives are manufactured to the highest levels of resolution, fluorescence brightness, and contrast; chromatic aberrations are almost eliminated. They are recommended for the most demanding applications, particularly at magnifications of 60x and above. Apochromatic objectives are the a great choice for the capture of color images in white light.

Brightfield contrast versus phase contrast objectives

Brightfield is the most basic form of light microscopy and is accomplished by sample absorption of light. A higher density area in a sample will absorb more light, thus increasing contrast in those areas.

Phase contrast objectives are most useful for hard to see, translucent specimens. This method of contrast is accomplished by converting phase shifts, caused by light passing through a translucent specimen, into brightness changes (i.e., contrast).

Long working distance versus coverslip-corrected objectives

Long working distance (LWD) objectives are optimized for use through vessels with a nominal wall thickness of 0.9–1.5 mm. This includes vessels commonly used in cell culture and cell-based assays, such as slides, cell culture dishes and flasks, microtiter well plates, etc. Coverslip-corrected objectives are optimized for use through #1.5 coverslips (thickness approximately 0.17 mm). These objectives have a higher magnification/NA ratio and provide higher resolution compared to LWD objectives.