Refractive index database

nk database   |   n2 database   |   about




Optical constants of HOYA - FD (Dense flint)

Wavelength: µm

Complex refractive index (n+ik)[ i ]

n   k   LogX   LogY   eV

Derived optical constants

Dispersion formula


Conditions & Spec sheet

n_is_absolute: false
wavelength_is_vacuum: false
temperature: 20.0 °C
  - type: "Schott formula"
    coefficients: -1.84917e-07 0.0 0.0 0.0 0.0 0.0
nd: 1.67270
Vd: 32.17
glass_code: 673322
density: 2.9 g/cm3
  - temperature_range: -30 70 °C
    coefficient: 8.9e-06 K-1
  - temperature_range: 20 300 °C
    coefficient: 1.09e-05 K-1
dPgF: 0.0059
climatic_resistance: 1.0
stain_resistance: 1.0
acid_resistance: 1.0


General glass Type


HOYA Zemax catalog 2017-04-01 (obtained from


[Expressions for n]   [CSV - comma separated]   [TXT - tab separated]   [Full database record]


SF5 optical glass

SF5 is a type of optical glass characterized by its high refractive index and moderate to high dispersion, indicated by a lower Abbe number. This makes it particularly useful in applications where significant light bending capabilities are needed, such as in the design of compact lenses. However, the higher dispersion means that it tends to separate different wavelengths of light more than other types of glass, which can lead to chromatic aberration if not properly managed. To counteract this, SF5 is often paired with other types of optical glass in complex lens systems to optimize performance across a range of wavelengths. Common applications for SF5 glass include high-quality camera lenses, microscopes, and other optical instruments where precise image quality is paramount. Though it is generally more expensive than standard optical glasses like BK7, its specialized properties make SF5 a valuable resource for optical designers aiming to achieve superior optical performance.

SF5 and similar glasses produced by different makers

Maker Glass
Schott N-SF5
Hikari E-SF5
Sumita K-SFLD5

HOYA Corporation

HOYA Corporation is a global technology company based in Japan, known for its diverse range of products in the fields of healthcare and optics. In the optical industry, HOYA is particularly recognized for its high-quality optical glass and lens technologies. The company produces a wide array of optical products, from eyeglass lenses with advanced coatings to specialized glass materials used in cameras, telescopes, and other precision optical instruments. HOYA's expertise extends to various types of optical glass, including low-dispersion and high-refractive-index materials, which find applications in situations requiring exceptional optical clarity and performance. Beyond its contributions to optics, HOYA has also ventured into medical technologies, making it a multi-faceted company with a broad impact. With a commitment to innovation and quality, HOYA has earned a reputation as a leader in its field, consistently delivering products that set industry standards for performance and reliability. Their expansive portfolio and technological prowess make them a go-to provider for both consumer and industrial optical solutions.

External links


Glass is a versatile, amorphous material that has been an essential component in optical technologies for centuries. Comprising mainly of silica along with various additives like soda, lime, or boron, glass can be engineered to exhibit a wide range of optical properties, such as refractive indices and dispersion characteristics. In the optical industry, specialized types of glass like crown, flint, and extra-low dispersion (ED) glasses are used for manufacturing lenses, prisms, and other optical elements. These glasses are precisely formulated to offer specific properties, such as low chromatic aberration or high light transmittance across different spectral ranges. Glass can also be coated with thin layers of materials like anti-reflective coatings to enhance its optical performance. More recently, advances in photonics and nanotechnology have led to the development of innovative glass types, such as photonic crystal and metamaterial glasses, which exhibit unique light-manipulating properties. It is crucial to note that the optical properties of glass, including its refractive index, can vary depending on its composition and temperature, making it important to consult specific data for particular applications. Overall, glass remains a foundational material in optics, its wide applicability owed to its tunable properties and general robustness.

External links