A Glossary Built on First Principles: Understanding Light & Sight

The driving light market is full of confusing specifications, misleading numbers, and marketing hype. This glossary is not a simple dictionary. It is designed to expose the myths and explain the scientific principles of what actually matters for your night-driving vision and safety.

Part 1: The Electrical Principles (Powering the Light)

Before you can have quality light, you must have sufficient power.

1. VOLTAGE

Voltage is the electrical "pressure" from your vehicle's battery (e.g., 12V). It "pushes" the electrical current (Amps) through the wiring to your light.

2. VOLTAGE DROP (The #1 Performance Killer)

This is the loss of electrical pressure (Voltage) as it travels through an inadequate wiring harness. Your battery may read 13.8V, but due to high resistance (Ohms), your bulb may only receive 10.5V. This starves the light of power, resulting in a dim, yellow, and severely underperforming beam.

This is why FYRLYT insists you must measure voltage at the bulb while it is ON. It is the most critical diagnostic test to ensure your wiring is not strangling your light's performance.

3. AMPS

So, if you know the total power (Watts) of a light and the voltage (Volts) of your system, you can find out how much current (Amps) it will draw.Amps (Amperes) are the volume or flow of electrical current.

AMPS = WATTS divided by VOLTS

A high-performance light like a FYRLYT MOFO 12000 requires a high current (Amps) to produce its 12,000 lumens, which is why a heavy-duty, low-resistance wiring harness is essential.

4. WATTS (W)

Watts are the unit of electrical power, measuring the energy consumed by the light.

WATTS = VOLTS X AMPS

Watts are often misunderstood and misused in marketing. A "low-watt" LED is not automatically "better" any more than a "high-watt" FYRLYT is "bad." Watts are simply the cost of entry for a specific level of performance. FYRLYT's high-wattage Xenophot bulb is the necessary "cost" to generate an extreme, 100-CRI lumen output that low-wattage LEDs cannot scientifically replicate.

5. OHMS

Ohms measure electrical resistance. In a wiring harness, high resistance is your enemy—it causes voltage drop. In a bulb's filament, resistance is the mechanism—it's what allows the filament to heat up and convert electrical energy into intense, 100-CRI light.

Part 2: The Light Measurements (Exposing the Myths)

Marketers sell you numbers. We want you to understand what they actually mean.

6. LUMENS (lm)

Lumens measure the total quantity of light emitted from a source. This is the "headline number" for marketers, but it's dangerously misleading for two reasons:

Raw vs. Effective: Most brands advertise Raw Lumens (a theoretical number from the LED chip) which is 30-50% higher than the Effective Lumens (the actual, real-world light output after heat and optical losses).

Quality vs. Quantity: A 20,000-lumen, low-CRI LED can be worse for vision than a 9,000-lumen, 100-CRI FYRLYT. Lumens tell you how much light there is, not how good it is for seeing detail.

7. THE "1 LUX @ 'X' DISTANCE" MYTH (EXPOSED)

The Claim: You will see "1 LUX @ 1200m" advertised as a measure of distance.

The Reality: 1 lux is the brightness of a single candle 1 metre away. It is functionally useless for identifying a hazard at speed. For comparison, a well-lit office is 300-500 lux. This marketing "spec" is a hypothetical, extrapolated number from a pin-point in the beam. It has zero relevance to real-world driving. It is, put simply, "snake oil" used to sell lights based on a meaningless number.

8. CANDELA (cd)

The modern (SI) scientific unit for luminous intensity, or the "punch" of a light in a single, specific direction. A high candela value means a very bright, focused hotspot.

9. CANDLEPOWER (cp)

An obsolete, older term for luminous intensity. 1 candlepower is approximately 1 candela. It is not a modern scientific unit and is only used in marketing to add confusion.

10. LUX (lx)

Lux measures the intensity of light on a surface. It answers the question, "How much light is actually arriving at an object?" This is the metric used in the "1 Lux Myth," but it is also the metric that would be useful if measured at a relevant brightness (e.g., "20 Lux @ 500m").

Part 3: The Visual Science (What Actually Matters)

This is the most important part. Stop buying a "light" and start investing in your "sight." These are the 4 scientific reasons FYRLYT's design ethos is superior.

11. CRI (COLOUR RENDERING INDEX)

This is the single most important metric for a driving light. CRI is a scale from 0-100 that measures a light's ability to reveal colours faithfully, just as natural daylight does.

100 CRI (FYRLYT / Halogen): Perfect colour reproduction. You see the brown kangaroo, the grey road, and the green foliage in their true, distinct colours. Your brain effortlessly identifies the hazard.

70-85 CRI (Typical LED): Compromised colour reproduction. The light spectrum is incomplete. The brown kangaroo/livestock and the road are "washed out" into similar muted tones. Your brain struggles to distinguish them, increasing eye strain and delaying reaction time.

12. VISUAL ACUITY

This is the scientific term for the clarity or sharpness of vision. High visual acuity means you can see fine detail, which is critical for identifying a distant object. High-CRI light (FYRLYT) delivers the full spectrum of colour information to your eye, providing superior visual acuity with less cognitive load. Low-CRI light from LEDs forces your brain to "fill in the blanks," reducing acuity.

13. THE TYNDALL EFFECT (Glare in Dust, Rain, Fog & Smoke)

This is a scientific principle describing how light scatters off fine particles.

High-Kelvin LED (Blue Light): Composed of short, aggressive wavelengths that scatter violently, reflecting off dust, rain, smoke or fog. This creates a blinding "white wall" of glare, forcing you to slow down.

FYRLYT Halogen: Composed of longer, more penetrating wavelengths (more red/yellow). This light cuts through particles with significantly less scatter, letting you see the road instead of the "white wall."

14. DARK ADAPTATION

This is your eye's ability to recover and see in the dark after you dip your high beams for oncoming traffic. The intense, narrow-spectrum blue light from LEDs "bleaches" the photoreceptors in your eyes, dramatically slowing your recovery time. FYRLYT's 100-CRI, balanced spectrum is far gentler, allowing for rapid dark adaptation and making you safer after dipping your lights.

15. KELVIN

Kelvin measures the colour temperature or appearance of light, from "warm" yellow to "cool" blue. It is often misused by marketers to imply quality. A 4000-5000+K "daylight" LED is not the same quality as actual daylight—it is a low-CRI, blue-spectrum light (which causes the Tyndall Effect) masquerading as daylight.

FYRLYT's 100 CRI Xenophot bulb has a pure, balanced spectrum that is not comparable to an LED of the same "Kelvin" rating.