Meiji MA527 Auxiliary Lens for EMT-1 / EMT-2 — 0.75X Magnification, 72mm Working Distance

The Meiji MA527 is a 0.75X auxiliary (supplementary) lens for Meiji EM-Series stereo microscope bodies. It is typically selected to increase working distance and improve tool/fixture clearance for hands-on inspection tasks while maintaining stronger detail capability than a 0.5X option. With a published working distance of 72mm, MA527 is a practical “scan + handle” configuration for QC benches, cleanroom workstations, and rework/assembly support.

Quick selection note: MA527 (0.75X) is a balanced clearance accessory—more space and coverage than 1.0X, while preserving more apparent detail than 0.5X for general-purpose inspection.

Specifications:

Accessory type: Auxiliary lens (auxiliary objective / supplementary lens)
Magnification factor: 0.75X
Working distance (W.D.): 72mm
Fits: EMT-2, EMTR-2, EMT-3, EMTR-3, EMT-4, EMTR-4
Important note: MA515 adapter is required to use MA527 on EMT-2

Where MA527 Fits in Cleanrooms and Laboratories (and Why)

MA527 is commonly chosen when the limiting constraint is clearance and handling (tools, tweezers, fixtures, gloved manipulation), but teams still want sufficient apparent detail for routine defect screening. In cleanrooms, improved clearance can also reduce accidental contact events with optics and work surfaces, supporting more consistent station discipline over long shifts.

Typical program fit: scan stations, assembly/rework benches, incoming inspection, and general-purpose QC inspection where ergonomics and throughput matter.

For process robustness, many facilities standardize a scan configuration (0.75X or 0.5X for clearance) and a separate confirm configuration for higher-detail decisions—reducing operator variability and decision drift.

MA527 Features:

0.75X auxiliary lens engineered for Meiji EMT/EMTR stereo microscope bodies
72mm working distance for improved clearance and bench ergonomics
Balanced configuration: clearance and coverage without an extreme magnification reduction
Supports standardized station roles (scan vs confirm) for consistent inspection outcomes

MA527 Benefits:

More clearance: better access for tools, fixtures, and gloved part handling under the objective.
Improved workflow speed: fewer repositioning cycles during scan-and-handle inspection tasks.
Better ergonomics: reduces operator fatigue and improves inspection consistency over time.
More balanced detail: preserves more apparent detail than 0.5X while still increasing working distance.

Common Applications:

Incoming inspection and scan workflows (coverage, orientation, and handling)
Assembly support and rework where tools must fit under the objective
General-purpose QC inspection where clearance and speed drive throughput
Cleanroom benches where reduced contact events improve station discipline

Selection Notes (0.75X vs. 0.5X vs. >1.0X)

MA527 (0.75X / 72mm W.D.): balanced clearance and detail for scan + handle stations.
MA518 (0.5X / 108mm W.D.): clearance-first for maximum tool access and large-part handling.
>1.0X options: selected when defect discrimination is the limiting constraint; working distance decreases and clearance tightens.

Optics Cleaning (Recommended for Stereo Objectives & Auxiliary Lenses)

Auxiliary lenses sit close to the work zone and can collect haze, particulate, and handling residues that reduce contrast. SOSCleanroom recommends optical-grade swabs and specialty low-lint wipers to maintain visibility without shedding fibers on coated optics.

Link to Meiji MA527 Product Details / Datasheet: Manufacturer Product Page | Datasheet (PDF)

Other Similar Products Available From SOSCleanroom.com

Meiji MA518 (0.5X / W.D. 108mm) — maximum clearance for tool-heavy benches
Meiji MA519 Super Widefield 10X Focusing Eyepiece — common bench accessory for focus control and reticle use (model-dependent)
Cleanroom Wipers — supports workstation cleaning and contamination control

Notes: Treat auxiliary lens factor as a configuration-controlled input. If benches use different factors, parts will appear at different apparent size and coverage—driving inspection inconsistency.

Product page updated: Jan. 21, 2026 (SOS Technical Staff)

© 2026 SOS Supply. All rights reserved.

The Technical Vault

By SOSCleanroom

Last reviewed: Jan. 21, 2026 | Audience: cleanroom operations, QA/QC, lab managers, manufacturing engineering, EHS

Why 0.75X Auxiliary Lenses Are “Balance Tools” in Stereo Microscopy

Meiji MA527 — 72mm working distance, scan/handle station design, and configuration control for consistent inspection decisions

Clearance + detail balance Scan vs confirm stations Stereo vs compound education

The one-paragraph answer

The Meiji MA527 is a 0.75X auxiliary (supplementary) lens for supported Meiji EMT/EMTR stereo microscope bodies that provides a 72mm working distance. In real inspection programs, 0.75X lenses are chosen to improve clearance and coverage while preserving enough apparent detail for routine defect screening—making them ideal for scan-and-handle benches. Note: MA515 adapter is required to use MA527 on EMT-2.

Operational problems MA527 helps solve

Insufficient clearance: tools/fixtures collide with the objective area during manipulation.
Slow cycle time: repeated repositioning to “fit under the lens” reduces throughput.
Operator fatigue: awkward posture increases inspection variability over long shifts.
Cleanroom discipline friction: cramped clearance increases incidental touches and contact events.

Microscopy education: stereo vs. compound microscope engineering

Stereo microscopes are engineered for inspection and manipulation. They use dual optical paths to provide depth perception and are commonly configured with stands, illumination, eyepieces, and auxiliary lenses to tune workflow constraints (clearance, coverage, and detail). MA527 is a stereo workflow accessory because stereo microscopy is often a production/QC tool where bench ergonomics directly affect consistency.

Compound microscopes are typically optimized for higher magnification analytical viewing (often slide-based) using a single optical axis and transmitted illumination. Their architecture prioritizes objective/condenser performance and optical alignment over tool clearance—ideal for analytical microscopy, but not the default solution for hands-on rework and manipulation tasks.

Why this matters: MA527 is a workflow optimization choice—more clearance for better bench behavior, while retaining meaningful detail for routine screening.

Best-practice bench design: “scan” vs “confirm” stations

Many inspection programs perform best when benches are assigned roles: a scan/handle station (clearance + coverage) for orientation and throughput, and a confirm station (higher apparent detail) for borderline calls. MA527 is commonly a scan/handle configuration; confirm benches typically use higher-factor configurations where clearance is less critical.

Configuration control (minimum recommended fields)

Microscope body model (EMT/EMTR series)
Eyepiece model/magnification
Auxiliary lens factor (MA527 0.75X)
Stand type and typical working height
Illumination type and typical intensity/geometry settings

Optics cleaning and contamination control

In cleanrooms and labs, optics artifacts (haze, fingerprints, film residues) can be misread as defects. Implement an optics-care routine using optical-grade swabs and low-lint wipers to maintain contrast and reduce fiber shedding on coated glass.

Suggested optics-cleaning SOP insert (template-style)

Remove loose particles prior to wiping to avoid dragging grit across coated optics.
Dampen a fresh optical swab/wiper with minimal approved solvent.
Wipe gently in one direction; avoid heavy pressure and repeated scrubbing.
Replace the cleaning surface frequently; do not reuse loaded swabs/wipers.
Cover the microscope when idle to reduce airborne deposition.

Helpful links

Source basis

SOSCleanroom product listing context (application positioning and program-fit language).
Manufacturer product page and datasheet for MA527 (0.75X factor, 72mm W.D., fit list, adapter note).
Common inspection microscopy best practices: scan vs confirm workflow design, configuration control, and optics hygiene discipline.

Compliance note: This Technical Vault article is provided for educational support. Always follow facility SOPs, QA requirements, and validation/qualification plans.

Document control: Rev. Jan. 21, 2026 (SOS Technical Staff)