VHG was founded in 1981 as an independent analytical testing laboratory. In 1984, VHG expanded its operation to include the commercial manufacture of high-purity single and multi-element calibration standards for spectroscopic instrumentation.

VHG has manufactured single and multi-element standards (both aqueous and oil-based) for more than 30 years, including petroleum standards, analytical reference standards for new and in-service oil applications, and standards for ASTM, DIN, IP, ISO, JIS and ANFOR methods, including EPA Tier 3.

Volume holographic gratings (VHG) provide the capability of narrowing and stabilizing the wavelength of semiconductor lasers by forming an external cavity laser (ECL). We are reporting on a novel self-aligned non-dispersive external cavity laser (ECL) based on thick volume holographic gratings (VHG).

VHG Aqueous Inorganic Certified Reference Materials (CRMs) & Calibration Standards

2024年10月29日 · 研究团队开发了一种双连续玻璃态聚合物异质凝胶（vhg），具有高机械强度、宽跨度可变刚度和双向离子压阻传感功能，为智能传感器、软体机器和生物电子设备提供了新材料基础。

VHG Hospitality is at the forefront of development and operations of tented camps and eco lodges in Asia. We provide turnkey, capital-efficient solutions for investors seeking to own exclusive tented camps, and will advise on locations in some of the region’s most captivating wilderness and beach destinations.

体布拉格光栅(VBG，VHG)，可被置于激光共振腔内用以对激光器波长锁定（中心波长精度为0.1-0.5nm ） 、横模纵模选取及控制、激光线宽压窄（低至20pm ）及提升激光器工作温度范围。

VHG ( Victoria Harbour Group / Victoria Harbor Group ) is named after Hong Kong’s iconic Victoria harbour, where the Group first convened. Our founders believe a city is defined by its people, and that central to what made Hong Kong were its freedoms and liberal values, which underpin a free, open and dynamic society.

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2023年5月23日 · 以光致聚合物制备的体全息光栅（VHG）作为耦合元件的全息光波导具有体积小、重量轻、成像清晰、设计灵活等优势，正受到AR研发领域的广泛关注。 为了实现高性能透明体全息光栅的制备，光致聚合物的折射率调制度（n）至少要高于0.02。 然而，目前文献报道的工作中只有很少量的全息光致聚合物能达到这个要求。 材料已成为制约该领域发展的最大技术瓶颈。 中国科学院理化技术研究所的新型功能聚合物组和应用激光研究中心合作，通过材料创新和配 …