Domain: Natural Science — Biophysics
Target concept: Chlorophyll extract in a transparent vial exhibiting fluorescence under ultraviolet light

Video generation prompt: A transparent glass vial containing green chlorophyll extract is illuminated by a handheld ultraviolet lamp, which is turned on and moved back and forth near and away from the vial.

Evaluation guide:
(i) Target concept: UV-induced fluorescence of chlorophyll a/b in solution
Minimum mechanism: Chlorophyll molecules must absorb UV photons (invisible to human eye) and emit detectable red-orange photons (600–750 nm); emission requires direct photon absorption: no fluorescence without UV excitation; emission must cease immediately upon excitation removal; green color arises from absorption of red/blue light in visible spectrum, unrelated to fluorescence.
(ii)Storyline: [Phase 1] Static shot: vial with green liquid under ambient light → green color visible, no glow. [Phase 2] Lamp enters frame, activates (purple/violet light appears), approaches vial → red-orange glow emerges *inside vial only*. [Phase 3] Lamp reaches closest point → glow peaks in brightness. [Phase 4] Lamp withdraws → glow fades synchronously and fully extinguishes before lamp exits frame. [Phase 5] Vial returns to ambient appearance (green only). All phases occur from fixed frontal viewpoint; vial never rotates or shifts; hand holding lamp remains partially visible and occludes lamp base when near vial; no secondary light sources illuminate vial during experiment.

Manual:
Experimental Procedure
1. Place a transparent glass vial filled with green chlorophyll extract on a neutral background.
2. Activate a handheld ultraviolet lamp and bring it close to the vial (within ~10 cm).
3. Slowly move the lamp back and forth — approaching, stopping near, withdrawing, repeating — for ~10 seconds.
Observation of Experimental Phenomena
When the ultraviolet lamp is near the vial, the green chlorophyll extract emits visible red-orange fluorescence; when the lamp is withdrawn, fluorescence ceases and only the green color of the liquid remains visible.
Summary of Experimental Principles
Chlorophyll absorbs ultraviolet light and re-emits energy as longer-wavelength red-orange fluorescence — a photophysical phenomenon demonstrating electronic excitation and radiative relaxation in biological pigments.

Prompt Grounding rubric:
level_1: The video shows no transparent vial with green chlorophyll extract and no handheld ultraviolet lamp at all: for example, only an empty background, a different container, or an unrelated scene with no lamp motion of any kind.
level_2: A transparent vial and a handheld lamp both appear, but the vial does not hold visibly green liquid, or the lamp is held stationary and never approaches or withdraws from the vial, or the lamp is never pointed toward the vial.
level_3: A transparent vial holding visibly green liquid is shown together with a handheld ultraviolet lamp that is switched on (glowing violet/purple) and brought near the vial and pulled away at least once, though the back-and-forth motion is irregular or not clearly aimed at the vial.
level_4: All of score 3 is satisfied, and additionally the lamp's near/far motion is smooth, repeated, and clearly directed at the vial along one path, the vial itself never changes position, and the green liquid stays visible when the lamp is not glowing.
level_5: All of score 4 is satisfied, and additionally the vial stays centered and stationary in frame for the whole clip, the lamp is visibly hand-held with no rig or arm supporting it, the lamp only begins moving after it is already lit, and nothing else in the shot blocks the view of either the vial or the lamp.

Scientific and Causal Correctness rubric:
level_1: The liquid never glows or changes appearance when the lamp is near it. The vial looks the same whether the lamp is close, far, on, or off.
level_2: The liquid changes appearance near the lamp, but incorrectly: e.g., it turns yellow, white, or blue instead of red-orange, or the color change happens while the lamp is off or pointed away, or a glow appears without the lamp being nearby at all.
level_3: A red-orange glow appears specifically when the lit UV lamp is close to the vial and disappears when the lamp is withdrawn; the underlying liquid still reads as green under normal (non-glowing) viewing, so the green color and the red-orange glow read as two distinct effects.
level_4: All of score 3 is satisfied, and additionally the red-orange glow stays confined to inside the vial (it does not spread onto the table, the lamp, or the hand), and the glow's brightness tracks the lamp's distance: brighter as the lamp nears, dimmer as it retreats.
level_5: All of score 4 is satisfied, and additionally the glow follows the lamp's movement with no noticeable lag as the lamp approaches and fades out promptly as the lamp withdraws, with nothing left glowing once the lamp is far from the vial; the green color of the liquid never shifts hue during ambient (non-glowing) moments, and the lamp's own violet light is never mistaken for the red-orange emission.

Spatiotemporal Consistency rubric:
level_1: The vial or the lamp jumps to a different position or orientation between moments with no continuous movement in between, or either object flickers out of existence and reappears, or the light/shadow pattern on the vial contradicts the lamp's actual position (e.g., a bright side that doesn't match where the lamp is).
level_2: The vial or lamp visibly warps, stretches, or flattens at some point, or the lamp's near/far motion stalls and skips ahead rather than moving continuously, or the violet lamplight itself blinks on and off during the sweep without the lamp being turned off.
level_3: The vial stays rigid and intact and the lamp is held consistently throughout; the near-to-far-to-near motion of the lamp is continuous rather than jumpy, and the highlights on the vial's glass shift smoothly as the lamp moves rather than jumping or freezing.
level_4: All of score 3 is satisfied, and additionally the lamp never passes through the vial or vice versa, the vial's glass shape never warps or shears from the camera's perspective, the background stays put, and the hand holding the lamp moves naturally, partly covering the lamp's base when it is close to the vial.
level_5: All of score 4 is satisfied, and additionally the camera never pans, tilts, or zooms, the vial stays in the same part of the frame the entire time, the lamp's apparent size and distance from the vial change believably as it moves, and there is no flicker, double-image, or blur that makes it hard to tell where the vial or lamp boundary is at any moment.