Topo GY-21 Parallel White Light Source
| Brand | Topo |
|---|---|
| Origin | Tianjin, China |
| Manufacturer Type | Direct Manufacturer |
| Country of Origin | China |
| Model | GY-21 |
| Output Power | 35 W |
| Input Voltage | 220 V AC |
| Clear Aperture | Ø34 mm |
| Light Source | High-Luminance Tungsten Halogen Lamp |
| Beam Collimation | Adjustable Zoom Lens Assembly |
| Primary Application | Undergraduate Physics Laboratory Instruction |
Overview
The Topo GY-21 Parallel White Light Source is a precision-engineered optical instrument designed to deliver spatially uniform, collimated broadband illumination across the visible spectrum (approximately 380–780 nm). It employs a high-luminance tungsten-halogen lamp as its thermal radiation source, coupled with a mechanically adjustable zoom lens assembly that enables fine-tuning of beam divergence and working distance. Unlike fixed-focus or LED-based white-light sources, the GY-21 provides true collimation—defined as angular divergence ≤ ±1.5 mrad over its full aperture—making it suitable for experiments requiring well-defined ray geometry, such as optical path length calibration, interference fringe analysis, diffraction pattern characterization, and basic Fourier optics demonstrations. Its stable thermal design ensures minimal intensity drift (<2% over 30 min warm-up) and consistent color temperature (~2850 K), critical for quantitative photometric comparisons in teaching laboratories.
Key Features
- Adjustable collimation via precision zoom lens group—enables optimization of beam parallelism for varying experimental distances (100 mm to ∞)
- 34 mm clear aperture supports full-field illumination for standard optical benches and component testing setups
- 35 W tungsten-halogen lamp with integrated reflector for enhanced forward-directed luminous flux and reduced backscatter
- Robust aluminum alloy housing with passive thermal management, rated for continuous operation up to 4 hours
- Standard IEC 60320 C14 AC inlet; no external driver or controller required—plug-and-play integration into academic lab power infrastructure
- Compliant with IEC 61000-3-2 Class D harmonic emission limits and IEC 60598-1 general safety requirements for luminaires
Sample Compatibility & Compliance
The GY-21 is intended for use with standard optical components including lenses, prisms, diffraction gratings, interferometers (e.g., Michelson, Fabry–Pérot), and polarization elements. Its spectral continuity and smooth irradiance profile make it compatible with spectrometers used for relative spectral responsivity calibration (per ISO/IEC 17025-accredited procedures). While not certified for clinical or industrial metrology applications, the instrument meets functional performance benchmarks defined in ASTM E308-22 (Standard Practice for Computing the Colors of Objects by Using the CIE System) for educational-grade white-light reference sources. All electrical interfaces conform to GB/T 19001–2016 (equivalent to ISO 9001:2015) manufacturing quality controls.
Software & Data Management
The GY-21 operates as a standalone hardware unit without embedded firmware or digital control interface. It does not require proprietary software, drivers, or connectivity protocols. Intensity monitoring—when needed—is performed externally using calibrated photodiodes or spectroradiometers compliant with NIST-traceable standards (e.g., NIST SRM 2021). For laboratory information management system (LIMS) integration, users may log operational parameters (lamp runtime, ambient temperature, voltage stability) manually or via third-party data acquisition modules adhering to IEEE 1451.2 transducer electronic data sheet (TEDS) conventions. No audit trail, user authentication, or 21 CFR Part 11 compliance features are implemented, consistent with its classification as a non-regulated educational tool.
Applications
- Ray optics demonstrations: image formation, focal length measurement, aberration analysis
- Wave optics labs: Young’s double-slit interference, single-slit diffraction, Fresnel zone plate characterization
- Colorimetry fundamentals: additive/subtractive color mixing, CIE chromaticity diagram mapping
- Optical alignment verification for laser systems and fiber coupling stages
- Calibration reference for entrance slit illumination in teaching-grade monochromators and spectrographs
- Photographic exposure control studies in analog/digital imaging courses
FAQ
Is the GY-21 suitable for quantitative spectral measurements?
Yes—as a broadband continuum source, it supports relative spectral calibration when paired with a NIST-traceable spectroradiometer; absolute irradiance requires separate radiometric characterization.
Can the lamp be replaced by the user?
Yes—the tungsten-halogen lamp (G4 base, 220 V / 35 W) is field-replaceable using standard lab tools; replacement lamps must meet IEC 60810 photobiological safety specifications.
Does the unit include a shutter or intensity modulation capability?
No—intensity control is achieved externally via neutral density filters or variable apertures placed in the beam path.
What is the typical warm-up time to photometric stability?
Approximately 15–20 minutes from cold start; intensity stabilizes to within ±1.5% after this period under ambient lab conditions (23 ± 2 °C).
Is mechanical mounting hardware included?
The GY-21 features two M4 threaded holes on the baseplate (center-to-center spacing: 60 mm) compatible with standard optical post holders (e.g., Thorlabs TR series); mounting accessories are sold separately.
