NLO Crystals

/KTP Nonlinear crystal Potassium Titanyl Phosphate

KTP Nonlinear crystal Potassium Titanyl Phosphate

Potassium Titanyl Phosphate (KTiOPO4 or KTP) is widely used in both commercial and military lasers including laboratory and medical systems, range-finders, lidar, optical communication and industrial systems.

  • Product Origin:

  • Shipping Port:

    Fuzhou, China
  • Lead Time:

Share To : f t y b l ins
  • Product Detail


KTP Nonlinear crystal Potassium Titanyl Phosphate is the most commonly used material for frequency doubling of Nd-doped lasers, particularly at the low or medium power density. It is widely used for frequency mixing to generate Red/Green/Blue output, and for OPO and OPA to generate visible to mid-infrared tunable output. It is also used for many E-O devices such as Q-switches and E-O modulators.

Main applications:

1) Frequency Doubling (SHG) of Nd-doped Lasers for Green/Red Output;

2) Frequency Mixing (SFM) of Nd Laser and Diode Laser for Blue Output;

3) Parametric Sources (OPG, OPA and OPO) for 600nm - 4500nm Tunable Ouptut;

4) E-O Modulators, Optical Switches, Directional Couplers;

5) Optical Waveguides for Integrated NLO and E-O DevicesOPA and OPO.


1) Large nonlinear optical coefficient;

2) Wide angular bandwidth and small walk-off angle

3) Broad temperature and spectral bandwidth;

4) High Electro-Optics(E-O) coefficient and low dielectric constant;

5) Non-hygroscopic, chemically and mechanically stable

Optical and Nonlinear properties of KTP crystal

Transparency Range


SHG Phase Matchable Range

497 ~ 1800nm (Type II)

Therm-optic Coefficient (/, λ in μm)


Absorption Coefficients

<0.1%/cm at 1064nm <1%/cm at 532nm

Angle Acceptance

14.2mrad·cm (φ);55.3mrad·cm (θ) for Type II SHG of a Nd:YAG laser at 1064nm

Temperature Acceptance

24°C·cm for Type II SHG of a Nd:YAG laser at 1064nm

Spectral Acceptance

0.56nm·cm for Type II SHG of a Nd:YAG laser at 1064nm

Walk-off Angle

0.55° for Type II SHG of a Nd:YAG laser at 1064nm

NLO Coefficients

deff(II)≈(d24 - d15)sin2Φsin2θ - (d15sin2Φ + d24cos2Φ)sinθ

Non-vanished NLO susceptibilities

d31=6.5 pm/V d24=7.6 pm/V
d32= 5 pm/V d15=6.1 pm/V
d33=13.7 pm/V

Sellmeier Equations (λ in μm)


Electro-optic Coefficients:






Low and High frequency (pm/V)

9.5 and 8.8

15.7and 13.8

36.3 and 35

7.3 and 6.9

9.3 and 8.8

Relative Dielectric Constant


Physical properties of KTP crystal

Crystal Structure

Orthorhombic, space group Pna21,point group mm2

Lattice Parameter

a=6.404Å, b=10.616Å, c=12.814A, Z=8

Melting Point

About 1172°C

Mohs Hardness



3.01 g/cm3

Refractive indices

nX = 1,7404; nY = 1,7479; nZ = 1,8296 @1064 nm

Thermal Conductivity


Thermal Expansion Coefficients

ax=11x10-6/, ay=9x10-6/, az=0.6x10-6/

HGO offers KTP specifications:

Tolerance of cutting angle


Tolerance of dimension

Dimension+0/-0.1 mmL±0.1mm


λ/10 @ 632.8nm

Wavefront distortion

λ/8@ 632.8nm

Surface quality

10/5 per MIL-O-13830A





Clear Aperture:

> 90%


< 0.1 mm @ 45°


Upon customer request


AR/HR coating upon customer’s request

Damage Threshold

750MW/CM2 at 1064nm, TEM00, 10ns, 10Hz

Quality Warranty Period

One year under proper use

Why Choose HGO ?

HGO can supply high quality potassium titanyl phosphate (KTiOPO4, KTP) nonlinear crystals. Size up to 20mm*20mm*40mm and length from 0.1mm up to 80mm.

Besides, HGO provides high grey track resistance HGTR-KTP crystals as a solution, which significantly improves the grey-track resistance and overall performance. HGTR-KTP crystals extend the use of KTP as a nonlinear medium to high-power applications.

Leave A Message
If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.
Related Products
Lithium Triborate (LiB3O5 or LBO Crystal)
LBO Nonlinear Optical crystal Lithium Triborate Crystal

HGO grows LBO Nonlinear crystals using flux technology. LBO crystals is an excellent nonlinear crystal.For frequency doubling(SHG),tripling(THG) of Nd:YAG,Nd:YLF,Nd:YVO4 lasers, it is one of the most useful nonlinear optical materials in ultraviolet and visible laser applications.

Read More
BBO Nonlinear crystal
BBO Nonlinear crystal Beta-Barium Borate Crystal

HGO grows BBO Nonlinear crystals using flux technology. BBO crystal transparency ranges from 188 nm to 5,2 µm, which includes reasonable transparency from 3-5,2 µm for few tens µm thick crystals, while their phase-matchable range spans almost over the entire transparency range. Combined with other magnificent properties of BBO, it is favorable for numerous nonlinear parametric applications. It is worth to mention that BBO crystals have the highest nonlinearity in the UV range out of all common nonlinear crystals.

Read More
LiNbO3 LN nonlinear crystal
LiNbO3 crystal Lithium niobate

LiNbO3 is widely used as electro-optic modulators and Q-switches for Nd:YAG, Nd:YLF and Ti:Sapphire lasers as well as modulators for fiber optics.

Read More
KDP & DKDP/KD*P Crystal
KDP & DKDP Crystal Potassium Dihydrogen Phosphate and Potassium Dideuterium Phosphate

KDP Potassium Dihydrogen Phosphate and KD*P or DKDP Potassium Dideuterium Phosphate are among the most widely-used commercial NLO materials, characterized by good UV transmission, high damage threshold, and high birefringence, though their NLO coefficients are relatively low. They are usually used for doubling, tripling and quadrupling of a Nd:YAG laser under the room temperature. In addition, they are also excellent electro-optic crystals with high electro-optic coefficients, widely used as electro-optical modulators, such as Q-switches, Pockels Cells, etc.

Read More
UV Fused Silica Double-Convex  Lenses
Double-Convex Lenses

Double Convex Lenses are used in image relay applications, or for imaging objects at close conjugates. Double Convex Lenses have positive focal lengths, along with two convex surfaces with equal radii. Aberrations will increase as the conjugate ratios increase.  Double-Convex Lenses are used in a range of industries or applications. HG OPTRONICS offers Double Convex lenses with a variety of coating options.

Read More
IPL Filters For Laser Beauty Machine
Fused Silica IPL Filter For Hair Removal

IPL Filter is the key optical element for IPL (intense Pulsed Light) machine, which blocks the UV wave and transmits the useful wave from 400nm to 1200nm for laser equipment, such as photo-rejuvenation hair removal, vascular and acne treatment, skin rejuvenation.

Read More
Plano-Concave Lens Manufacturer
Optical Glass Plano-Concave Lenses

Plano Concave Lenses are ideal for beam expansion, light projection, or for expanding an optical system's focal length. Plano Concave Lenses, which have one concave surface, are Optical Lenses with negative focal lengths. Plano-Concave Lenses should be shaped with the plano, or flat, surface towards the desired focal plane.Plano-Concave Lenses are ideal for use in a range of applications or industries. HG OPTRONICS offers Plano-Concave lenses with a variety of coating options.

Read More
N-BK7 Plano Convex Circular Cylindrical Lenses
Optical Glass Plano Convex Circular Cylindrical Lenses

Plano-convex circular cylindrical lenses are useful for line imaging or uni-axial magnification in a wide range of applications. These lenses may be combined with other lenses to form complex imaging systems.

Read More
Leave A Message
Leave A Message
If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.