Corn Bulb is a type of LED light bulb — its name comes from its appearance: dozens of small LED chips are arranged around a long, cylindrical body, which looks like a corn cob.
Key facts
- Structure: A linear array of many tiny LED chips (SMD) mounted around a central column, often enclosed in a glass or plastic tube, with a screw base (usually E27 or E40, sometimes E14).
- How it works: Multiple small LEDs spread light in 360°, giving wide, even illumination without a single bright hotspot.
- Typical uses: High-bay warehouse lighting, street lights, floodlights, parking lots, garages, factory floors — places needing high brightness from compact fixtures. Also common as retrofit replacements in existing fixtures.
- Common specs: 5W–200W+ equivalents, available in warm white (2700–3000K), neutral (4000K), and cool white (5000–6500K); many are dimmable and rated for long life (25,000–50,000 hours).
Main pros / cons
| Pros | Cons |
|---|---|
| Bright, wide 360° light distribution | Larger/odd shape — may not fit enclosed or decorative fixtures |
| Energy efficient vs. halogen/CFL equivalents | Heat dissipation can be weaker in fully enclosed housings |
| Low cost, easy retrofit into existing screw sockets | Not a "pretty" bulb — strictly functional |
| Good lumen output per watt | Quality varies a lot by chip brand and driver |
Most corn bulbs use SMD chips (2835, 3030, 5050 etc.); the chip count per row × number of rows roughly determines wattage.
2. By Base Type (screw socket)
| Base | Diameter | Where it's common |
|---|---|---|
| E27 | 27 mm | Standard home/industrial fixtures worldwide |
| E40 | 40 mm | Large high-bay, street lamps, floodlights (high wattage) |
| E14 | 14 mm | Small decorative fixtures (less common for corn bulbs) |
| B22 | Bayonet | UK, India, Commonwealth markets |
3. By Power Source / Driver
| Type | Description |
|---|---|
| Built-in driver (AC direct) | 85–265V AC input, driver integrated in base — plug-and-play retrofit |
| External driver | Bulb body only, driver/igniter separate — used in street-light retrofit kits |
| Low-voltage DC | 12V/24V — solar lights, vehicles, off-grid systems |
4. By Special Features
- Dimmable — needs a compatible dimmable driver (check flicker performance)
- Photocell / daylight sensor — auto on/off for street and garden lights
- CCT switchable — one bulb, toggle between 3000K/4000K/6000K
- Motion sensor — for corridors, warehouses, security lights
- Enclosed-fixture rated — specifically designed to survive sealed housings with poor heat dissipation
Quick selection rule of thumb: For a retrofit into an existing street/high-bay fixture, you'll almost always want a 360° E40 (or E27) AC corn bulb with built-in driver; for directional lighting, choose 180°; for solar applications, choose DC voltage.
Corn bulbs are utility lighting — designed for high brightness and broad coverage rather than looks. Their main applications:
Typical Applications:
| Setting | Why corn bulbs fit |
|---|---|
| Street & road lighting | High lumen output, wide 360° spread, E40 retrofit into existing street-lamp housings |
| Warehouses & factories | High-bay and low-bay fixtures; bright, even light from tall ceilings |
| Parking lots & garages | Large-area coverage with fewer fixtures |
| Floodlights / security lights | High wattage (100W–200W+) for perimeter illumination |
| Retail & showrooms | Bright general lighting; available in warm/neutral/cool whites |
| Gyms, arenas, workshops | Durable, energy-efficient replacement for metal-halide or HPS lamps |
| Solar street light systems | DC-voltage versions (12V/24V) pair with solar panels and batteries |
| Home garages, basements, sheds | Cheap retrofit upgrade from old fluorescent/incandescent |
Why they're used as replacements
Corn bulbs are most popular as retrofit lamps — they screw directly into existing fixtures (especially ones made for older high-intensity discharge or fluorescent lamps) without rewiring the whole fixture:
- Directly replaces metal halide / HPS bulbs in the same E27/E40 socket
- Much lower energy consumption for equal or better light output
- Instant full brightness (no warm-up time like HPS)
- Long lifetime (25,000–50,000 hours) means fewer replacements at height
When they're NOT the right choice
- Decorative/visible fixtures (the cob shape is functional, not attractive)
- Enclosed airtight fittings without heat-rated design (overheating shortens life)
- Spaces needing narrow beam optics (use spotlights/reflector bulbs instead)
Call +1 718-688-9188 to speak with a US-based lighting professional expert or browse LED light bulb Solutions at www.jcelighting.com
