LFM LAB / PUT THE FOUR CONCEPTS TO WORK
First independent experiment
Resolve a close bead pair, capture a clear image, and report a calibrated distance.
Operate the microscope
Loading the 3D microscope…
Shutter closed: light stops at the shutter. Faint lines mark the available route.
Packets show the direction of travel in slow motion. The detector preview predicts the next exposure.
Working principle · 1. Excitation source
1. Excitation source
Provides the excitation light. Increasing intensity increases the photon rate, not the speed of light. This widefield model does not simulate a focused laser scanning the specimen.
Current controls: 20× / 0.45 · air · focus 1.50 µm · 8% excitation · 80 ms exposure · detector gain 1
Expanded cutaway; excitation and emission are slightly separated in the drawing to show their opposite directions through the same objective; packet speed, count and size are illustrative. Specimen focus motion is enlarged. The condenser beneath the slide belongs to transmitted illumination and is not used by this epi-fluorescence route.
Fluorescence working principle · reference ↗Predicted preview · shutter closed
Close-pair detail · enlarged 32 × 32 pixel crop.
Display enlargement adds no optical resolution.
Upper pair: 20 µm reference · middle: measure its centres · bottom: 0.70 µm resolution challenge.
Only live illumination and capture add simulated dose. This preview predicts an exposure while the shutter is closed.
Measure the saved capture
Capture settings stay fixed here when you adjust the microscope. A new capture replaces this image and clears its calibration.
Capture an image to unlock calibration and measurement.
Explain your choices
Model and assessment assumptions
This exercise uses the LFM lab’s synthetic fluorescence image engine: Gaussian emitter profiles broaden with defocus, photon and read noise affect raw counts, and clipping occurs before display mapping. The original six-bead phantom is in one plane, with 520 nm emission. Optical estimates are idealized. Detector gain scales counts before ADC clipping; the image display itself stays fixed. The 3D instrument is an explanatory schematic; measurements use saved 512 × 512 source pixels. The dose budget is a teaching constraint, not a physical damage limit. Pass requires all six criteria. The 20 µm reference and the middle pair must each be measured centre-to-centre.