Description
What’s Included
- Haag-Streit Stereo Variator beam splitter for BQ 900 (as photographed)
- Mounting hardware for BQ 900 microscope head
- 90-day Digital Eye Center warranty
Condition & Warranty
Used. Inspected and tested before listing — optical alignment confirmed and the variator’s lever / stereo-angle mechanism verified functional. Cleaned. Some signs of usage may be visible in the product photos. Covered by a 90-day warranty on parts and workmanship.
Haag Streit Stereo Variator — Used BQ 900 Accessory
The Haag Streit Stereo Variator is a clinical accessory unique to the Haag-Streit BQ 900 platform. Its function is to reduce the slit lamp’s stereoscopic observation angle from the standard 13° down to 4.5°, which is what makes stereoscopic fundus, peripheral retinal, and vitreous examination possible through small pupils and in high myopia — exactly the patients where standard slit-lamp posterior-segment exam is hardest. This used haag streit stereo variator ships inspected, with a 90-day warranty.
Without the variator, the BQ 900’s parallel optics give a beautiful stereoscopic anterior-segment view but cannot consistently access the posterior pole through narrow pupils. The variator narrows the convergence angle so both observation channels can pass through a smaller anatomical aperture together — turning the BQ 900 into a true stereoscopic fundus slit lamp. This is the reason teaching practices and retina-aware ophthalmologists choose the BQ 900 over simpler 2-step lamps.
Per a National Library of Medicine-indexed reference (Curr Probl Ophthalmol, 2015), stereoscopic slit-lamp fundus examination is a documented clinical technique for posterior-segment evaluation, and the optical adjustments enabled by accessories like the Stereo Variator directly support this workflow.
Why the Stereo Variator Matters
Reduces stereo angle 13° → 4.5° — the geometric trick that turns a routine slit lamp into a posterior-segment fundus tool.- Unique to the BQ 900 — this accessory is engineered specifically for the BQ 900 microscope head; it doesn’t fit BM 900, BD 900, or BC 900 platforms.
- Enables fundus exam through small pupils — geriatric, diabetic, and pharmacologically un-dilated patients become accessible.
- High myopia handling — narrower stereo angle reduces the optical penalty when working through high-minus refractions.
- Vitreous and peripheral retina visualization — stereoscopic depth at the posterior pole, not just anterior segment.
- Modular Haag-Streit ecosystem — slots into the standard BQ 900 microscope mount; coexists with beam splitters, observer tubes, and camera adapters.
- Clinical accessory, not a camera mount — the variator changes the user’s view through the eyepieces; it is NOT a camera or photo accessory.
Clinical Applications
- Stereoscopic fundus examination through small pupils (geriatric, post-cataract un-dilated, pharmacologically constricted)
- Peripheral retinal evaluation as part of routine slit-lamp exam
- Vitreous evaluation — strands, opacities, post-vitrectomy assessment
- Examination of high-myopic patients where standard 13° angle is too wide
- Pediatric posterior-segment exam where small pupil and patient cooperation make BIO difficult
- Teaching environments — demonstrating the difference between anterior and posterior stereoscopic exam techniques
Who This Is For
- Practices already running a Haag-Streit BQ 900 who want to add posterior-segment capability without a separate BIO setup
- Retina specialists who use the BQ 900 as a primary slit lamp and want stereoscopic vitreous/fundus exam at the same lane
- Teaching practices and residency programs explaining the optical principles of stereoscopic biomicroscopy
- Group practices acquiring used BQ 900 accessories to complete an existing BQ 900 platform
Technical Specifications
| Spec | Detail |
| Type | Stereo Variator (BQ 900 microscope accessory) |
| Function | Reduces stereoscopic observation angle from 13° to 4.5° |
| Compatibility | Haag-Streit BQ 900 slit lamp ONLY (not BM/BD/BC 900) |
| Optical purpose | Stereoscopic fundus, peripheral retina, vitreous examination |
| Use case | Small pupil, high myopia, undilated posterior segment |
| Mount | Standard BQ 900 microscope head interface |
| Manufacturer | Haag-Streit (factory accessory) |
| Condition | Used — inspected, mechanism tested |
| Warranty | 90 days (parts and workmanship) |
Compare BQ 900 Microscope Accessory Options
| Feature | Stereo Variator (this listing) | Short Observer Tube + Splitter | Beam Splitter Set BQ900/BX900 (new) |
| Primary purpose | Stereo angle reduction for fundus exam | Teaching / co-observation (50/50 split) | Camera mount (digital imaging) |
| Modifies user’s view | Yes — narrows convergence | No — duplicates the view to a 2nd observer | No — diverts to a camera |
| Includes camera mount | No | No | Yes |
| Best use case | Posterior segment / fundus exam | Resident / fellow training | Adding photo/video to BQ 900 |
| Compatible slit lamp | BQ 900 only | BQ 900 | BQ 900 / BX 900 |
| Condition / Warranty | Used / 90 days | Used / 90 days | New / 1 year |
| Price | $1,100 | $1,980 | $3,378 |
Looking for a teaching/observer attachment instead of a fundus accessory? See the Haag-Streit Short Observer Tube w/ Splitter. Need a camera-mount beam splitter? Compare with the brand-new Beam Splitter Set for BQ900/BX900. Don’t have a BQ 900 yet? See the used BQ 900 with AT 900 Tonometer at $9,900.
Questions about the Stereo Variator? Contact us to confirm BQ 900 microscope head compatibility before purchase — call 305-771-4562 or use the contact form.
