YANRUN SM-4L Continuous Zoom Stereo Microscope

Overview

The YANRUN SM-4L Continuous Zoom Stereo Microscope is an upright, Greenough-type stereoscopic optical instrument engineered for high-fidelity three-dimensional observation of macro-to-mesoscale specimens in industrial inspection, quality control, electronics assembly, metallurgical sample evaluation, and educational laboratory settings. Based on a dual-optical-path zoom system with coaxial parfocal design, the SM-4L delivers seamless magnification continuity from 7X to 45X without intermediate lens switching—enabling stable depth perception and consistent focus across the entire range. Its fixed 10X wide-field eyepieces (Φ20 mm) paired with a continuously variable objective zoom lens (0.7X–4.5X) ensure precise optical alignment, minimal chromatic aberration, and reproducible image geometry. With a standard working distance of 88 mm and vertical column travel exceeding 240 mm, the microscope accommodates bulky or irregularly shaped samples—including castings, PCBs, solder joints, and polished metallographic sections—without requiring frequent repositioning.

Key Features

• Continuous zoom optical path delivering true stereoscopic imaging with constant depth of field and parfocality across 7X–45X magnification
• Rugged aluminum alloy mechanical structure with precision-ground focusing mechanism and calibrated coarse/fine dual-speed focusing controls
• Fixed 10X wide-field eyepieces (Φ20 mm) optimized for extended visual fatigue-free observation; optional reticle eyepieces support manual measurement (0.1 mm per division)
• Modular auxiliary objective compatibility: 0.5X (WD = 137 mm), 0.75X (WD = 103 mm), 1X (WD = 88 mm), 1.5X (WD = 48 mm), and 2X (WD = 29 mm) for extended working distance or higher resolution imaging
• Dual illumination options: 8 W adjustable-intensity LED ring illuminator (90–265 V AC, working distance 35–200 mm) and 5 W fluorescent ring illuminator (110/220 V AC) for low-heat, shadow-minimized surface illumination
• Three base configurations (SM-4LA, SM-4LB, SM-4LC) accommodate varying workspace constraints and stage mobility requirements—including optional 42 × 42 mm XY translation stage

Sample Compatibility & Compliance

The SM-4L is designed for non-destructive macroscopic examination of opaque, reflective, or semi-reflective specimens typical in metallurgy, mechanical engineering, and electronics manufacturing. Its long working distance and large depth of field make it suitable for inspecting rough-cast surfaces, heat-treated alloys, brazed joints, and machined components per ASTM E3, ISO 4967, and GB/T 13298 standards. While not certified to ISO/IEC 17025 or equipped with automated calibration traceability out-of-the-box, the instrument’s mechanical stability and optical repeatability support routine use in GLP-aligned environments when integrated into documented SOPs. Optional reticle eyepieces and auxiliary objectives enable semi-quantitative dimensional assessment compliant with internal QA protocols.

Software & Data Management

The SM-4L operates as a standalone optical platform with no built-in digital imaging or proprietary software. It does not include a camera port or native USB interface; however, third-party C-mount adapters (e.g., 0.5X or 1X relay lenses) may be retrofitted to attach industry-standard CMOS sensors (e.g., Sony IMX series) for documentation purposes. Users integrating digital capture must validate image scale calibration independently using NIST-traceable stage micrometers. No firmware, audit trail, or FDA 21 CFR Part 11 compliance features are provided—consistent with its classification as a manual optical inspection tool rather than a regulated analytical instrument.

Applications

• Metallographic specimen screening prior to etching or microhardness testing
• Visual inspection of weld integrity, porosity, and inclusion distribution in castings and forgings
• PCB rework verification, solder joint morphology assessment, and component placement accuracy checks
• Tooling and die inspection for wear patterns, edge chipping, and surface finish anomalies
• Forensic material comparison, counterfeit part identification, and failure analysis triage
• Classroom instruction in materials science, mechanical engineering, and applied optics

FAQ

Does the SM-4L include a digital camera or image analysis software?
No. The SM-4L is a purely optical microscope without integrated imaging hardware or analysis software. Digital documentation requires external camera adaptation and third-party image processing tools.
Can the SM-4L be used for quantitative measurement?
Yes—when equipped with optional reticle eyepieces (0.1 mm/div) and calibrated using a stage micrometer, users can perform manual comparative measurements within ±5% uncertainty under controlled lighting and operator training.
Is the microscope compatible with fluorescence observation?
The optional 5 W fluorescent ring illuminator provides cold white light illumination but is not configured for excitation/emission wavelength separation; therefore, it does not support fluorescence microscopy applications.
What is the maximum specimen height that can be accommodated?
With full column extension (H < 265 mm) and standard 1X objective, the effective vertical clearance between stage and objective nosepiece exceeds 180 mm—sufficient for most industrial parts and mounted metallographic samples.
Are replacement parts and service support available internationally?
YANRUN provides OEM spare parts (eyepieces, objectives, illuminators, mechanical components) with lead times averaging 4–6 weeks for overseas delivery; technical documentation is supplied in English, and remote troubleshooting assistance is available upon request.