Dongguan Felix Glass Co., Ltd. E-mail: james@felixglass.com - Tel: +86 185 6503 2888
Home / All / Felix Glass | Subsea Optical Dome Port FAQ Library / 1.What Material Is Best for Subsea Optical Dome Port? | Felix Glass

1.What Material Is Best for Subsea Optical Dome Port? | Felix Glass

Update Time:2026/10/16

What material is best for subsea optical dome port?

Selecting the right substrate is critical for subsea dome port performance, pressure resistance and service life. The three common optical materials are C-axis Sapphire, JGS1 Fused Silica and BK7 optical glass. Acrylic is not recommended for deep-water pressure applications.

C-axis Sapphire

Sapphire is the top choice for 7000m abyssal deployment. It features outstanding compressive strength, excellent scratch resistance and stable optical transmission under high hydrostatic pressure. It resists seawater corrosion well. The main downside is higher raw material and machining cost.

JGS1 Fused Silica

JGS1 fused silica is ideal for 3000m mid-depth ROV and AUV projects. It delivers balanced optical performance, good seawater resistance and competitive pricing. For 7000m service, fused silica dome needs reinforced wall geometry and full FEA validation before production.

BK7 Optical Glass

BK7 has lower compressive strength. It is only acceptable for short-duration, shallow-water missions with strict annealing treatment. Not suitable for 7000m ultra-deep use.

Acrylic PMMA

Acrylic suffers creep deformation under high pressure. It is forbidden for 3000m and 7000m subsea dome applications.

Quick Material Selection Guide

  • 7000m long-term deep sea → C-axis Sapphire
  • 3000m commercial inspection ROV → JGS1 Fused Silica
  • Short mission, limited budget, shallow depth only → BK7 (with limitation)

FAQ

Q: Is sapphire better than fused silica for underwater dome?
A: Sapphire has superior compressive strength for ultra-deep 7000m. Fused silica offers cost advantage for mid-depth 3000m projects.

Q: Can BK7 glass be used for 7000m dome port?
A: No, BK7 does not have enough compressive strength for 700 bar pressure.

Q: Does seawater corrode fused silica or sapphire?
A: Both materials have excellent resistance to seawater corrosion.

Q: Can we add AR coating on sapphire and fused silica domes?
A: Yes, broadband AR anti-reflection coating can be applied on both substrates.

Q: Are your dome ports custom size?
A: Yes, custom diameter from 20mm to 60mm available.

CTA: Tell us your working depth and target wavelength, our engineers recommend suitable material for your optical dome port.

Related Subsea Dome Products

3000m Deep Sea Optical Dome Port

7000m Ultra Deep Sea Optical Dome Port

Flanged Optical Dome Port | Integrated One-Piece Flange Subsea Dome

Need Custom Subsea Optical Dome Port?

Tell us your working depth and target wavelength, our engineers recommend suitable material for your optical dome port.

Get Material Recommendation

Related reading: What is FEA simulation for subsea dome port?

Related reading: Hydrostatic Pressure Test for Subsea Dome Port

Related reading: Standard Dome vs Integrated Flanged Dome Port

Related reading: Optical Dome Diameter Tolerance & Surface Specifications

Related FAQ: Subsea Optical Dome Port FAQ Library

Related reading: 3000m vs 7000m vs Flanged Optical Dome Port: How to Choose Subsea Dome

James Fu, Sales Director of FELIX OPTICAL GLASS, and a poster displaying contact information for an optical glass deep-processing factory.James Fu, Sales Director of FELIX OPTICAL GLASS, and a poster displaying contact information for an optical glass deep-processing factory. 2
Learn more from our FAQ
What is the minimum order quantity for custom precision optical glass components?

FELIX OPTICAL GLASS offers highly flexible MOQs to support customer projects, including prototype testing, small-batch trial orders, and high-volume production. All products can be fully customized to your drawings, tolerances, and application standards. Please send us your specifications, and we will reply within 1-5 hours and provide an accurate quotation after careful evaluation within 1-2 days.

Can I get free glass samples for testing before bulk order?

Yes, our FELIX GLASS factory supports sample testing for a wide range of precision optical glass components and assemblies. The lead time for sample production is 3 to 7 working days. Please contact us today to arrange samples and obtain a customized solution that meets your needs.

What is the production lead time for custom optical glass components?

A: The production cycle for standard samples is 3-10 working days, while mass production requires 15-35 working days, depending on the complexity of the product and the order quantity. We provide reliable precision optical glass components and fast delivery services for orders from industries such as defense, industrial equipment, medical devices, shipbuilding, robotics, automotive, and aerospace. Please submit your project details so we can provide you with an accurate delivery schedule.

Are your optical glass products ISO, CE and RoHS certified?

All precision optical glass components from FELIX OPTICAL GLASS comply with ISO quality system standards as well as CE and RoHS requirements. We provide comprehensive test reports, spectral graphs, material certificates, and inspection documents for customer review. Please feel free to request complete certification details and a formal quotation at any time.

Do you offer one-stop custom optical glass processing services?

Yes. We offer a full range of precision optical glass component processing services, including CNC machining, precision grinding, optical polishing, chemical/physical tempering, vacuum coating (AR anti-reflective coating, AF anti-fingerprint coating, AG anti-glare coating, IR infrared coating), and screen printing. From raw materials to finished products, every step is completed in our own factory. Please tell us your needs, and we will provide you with the most cost-effective solution.

CONTACT US NOW FOR A QUOTE
We will respond promptly within 1 to 5 hours and provide an optimal, formal quotation within 1 to 2 days. Partnering with us is the smartest choice—start a mutually beneficial partnership today!
*Email
Name
*Title
*Content
Upload
  • Only supports .rar/.zip/.jpg/.png/.gif/.doc/.xls/.pdf, maximum 20MB.
Address

With 19 years of experience as a precision optical glass expert, we provide comprehensive and satisfactory customized solutions.

Navigation
News