The UPLSAPO 30x and 60x objectives are said to improve optical performance for live cell confocal, widefield fluorescence, multiphoton, differential interference contrast (DIC) and other applications.
These silicone oil objectives provide bright, high-resolution images from deep samples.
They are useful in long-term imaging experiments where, in the past, water evaporation may have been an issue.
The 30x, 1.05 NA, 0.8mm working distance and 60x, 1.3 NA, 0.3mm working distance objectives reduce loss of contrast due to spherical aberration when compared to conventional oil objectives.
By reducing the mismatch between the refractive index of the specimen and that of the immersion medium into which the objective is dipped, they provide higher resolution and brightness when imaging into thick samples.
While water immersion lenses are traditionally used to reduce refraction index mismatch, they are not practical for long-term, time-lapse imaging because of evaporation and low viscosity.
Glycerol immersion optics have been used as a substitute for water, but glycerol is not ideal because it tends to draw moisture from the air, resulting in changes in refractive index over time.
Silicone oil is very stable and does not have these issues; it more closely matches the refractive index (N=1.404) of intracellular components, making the new objectives useful for imaging into cells and for long-term, time-lapse experiments.
The objectives also feature a correction collar, enabling the user to correct for the spherical aberration that is present when imaging into a specimen beyond the cover slip.
Image resolution and contrast, along with fluorescence performance, are optimised and maintained by adjusting this collar.
