Optical Glass for Automotive Cameras

Automotive Camera Design and Chemical Durability
Since many automotive cameras are affixed to the outside of vehicles, high chemical durability is needed for the front lens in particular.  When the chemical durability of the glass is good, the cloudiness due to corrosion on the lens surface is minimal even when in contact with outside air and therefore provides continued clear lens visibility.
Open Chemical Durability with Powder Method
Glass types with good Water resistance [RW(p)] Automotive Glass Water Resistance Glass types with good Acid resistance [RA(p)] Glass types with good acid resistance
Open Automotive Camera Lens and Impact Strength
Automotive cameras that are mounted outside of the vehicle are likely to be in contact with atmospheric dust and small rocks kicked up by other vehicles nearby. This may adversely affect camera lenses with scratches occurring on the surface of the lens. Therefore optical glass types which are not easily scratched should be included in front lens design.Automotive Camera Lens and Impact Strength Glass types to consider that have good Impact Strength
Type Code nc nd nF ng vd s.g. Coloring
S-BSL7 516641 1.51386 1.51633 1.52191 1.52621 64.14 2.52 330/285
S-FSL5 487702 1.48534 1.48749 1.49228 1.49596 70.23 2.46 300/265
S-LAH55VS 835427 1.82899 1.83481 1.84852 1.85955 42.74 4.58 395/320
S-LAH65V 804466 1.79882 1.80400 1.81608 1.82569 46.58 4.72 385/315
S-LAH65VS 804465 1.79882 1.80400 1.81610 1.82573 46.53 4.46 380/310
S-LAL21 703524 1.69895 1.70300 1.71237 1.71976 52.38 3.85 395/320 More Info
S-LAL54Q 651562 1.64747 1.65100 1.65905 1.66532 56.24 3.36 385/- More Info
S-PHM52Q 618633 1.61550 1.61800 1.62479 1.63008 63.32 3.51 365/325
 
Open Thermal Shock Resistance
Automotive cameras are set in various places both inside and outside of the vehicle. Since cars are used in environments where the temperature range can vary widely from below zero in colder climates to more than 50�C inside a car on a summer day, temperature change and thermal shock can drastically affect the imaging functionality of the camera lenses. In some cases, thermal stress can even lead to cracks in a lens. Therefore refractive index fluctuations should certainly be a consideration. By designing the automotive camera system to include optical glasses developed with thermal shock in mind, adjustments to temperature change can be handled within the optical system efficiently. Thermal Shock Resistance Glass types to consider that have good Thermal Shock Resistance
Type Code nc nd nF ng vd s.g. Coloring
S-BSL7 516641 1.51386 1.51633 1.52191 1.52621 64.14 2.52 330/285
S-FSL5 487702 1.48534 1.48749 1.49228 1.49596 70.23 2.46 300/265
S-LAH55V 835427 1.82898 1.83481 1.84852 1.85956 42.73 4.73 400/325
S-LAH65V 804466 1.79882 1.80400 1.81608 1.82569 46.58 4.72 385/315
S-LAL21 703524 1.69895 1.70300 1.71237 1.71976 52.38 3.85 395/320 More Info
S-LAL7 652585 1.64821 1.65160 1.65934 1.66537 58.55 3.73 345/275
S-LAL54Q 651562 1.64747 1.65100 1.65905 1.66532 56.24 3.36 385/- More Info
S-LAM60 743493 1.73865 1.74320 1.75372 1.76205 49.34 4.06 375/330
S-TIM8 596392 1.59103 1.59551 1.60621 1.61501 39.24 2.63 380/350
 
Open Thermal Coefficient of Refractive Indices � dn/dT
When the surrounding temperature changes, refractive indices may change as well. This refractive indices change is known as thermal coefficient of refractive indices, or dndT, and can vary depending on wavelength and/or temperature range. Automotive camera lens systems are set in various places both inside and outside of the vehicle. Since cars are used in environments with wide ranges in temperature, the refractive indices of the lens can change. As a result, the focal point can often shift and it may be impossible to obtain clear images. Therefore it is crucial to design automotive camera lens systems using a combination of optical glasses that do not change, even if the surrounding temperature does. Thermal Coefficient of Refractive Indices – dn/dT dn/dT and Optical path length Change in temperature could cause a change in the refractive indices of optical glass and the material may expand as well. Therefore, in order to examine how the optical path length can change, both dn/dT and Coefficient of thermal expansion need to be considered. The relation between dn/dT and Coefficient of thermal expansion for Optical path length is as follows: dn/dT and Optical path length Glass types to consider that have unique dn/dT
Type Code nc nd nF ng vd s.g. Coloring
S-FPL55 439948 1.43733 1.43875 1.44196 1.44444 94.66 3.59 335/290
S-LAH52Q 800422 1.79389 1.79952 1.81282 1.82356 42.24 4.47 390/335 More Info
S-LAH53V 806409 1.80026 1.80610 1.81995 1.83121 40.93 4.41 400/345
S-LAH60V 834372 1.82740 1.83400 1.84981 1.86283 37.21 4.43 430/350
S-LAH88 917316 1.90803 1.91650 1.93703 1.95418 31.60 4.74 (400)/355
S-LAL20 699511 1.69520 1.69930 1.70888 1.71647 51.11 4.38 370/310 More Info
S-LAM3 717479 1.71253 1.71700 1.72749 1.73587 47.92 4.25 385/340
S-LAM73 794371 1.78732 1.79360 1.80872 1.82119 37.09 4.45 415/350 More Info
S-NPH1W 808228 1.79801 1.80809 1.83351 1.85590 22.76 3.29 420/375
S-NPH7 778239 1.76902 1.77830 1.80157 1.82191 23.91 3.30 420/370 More Info
Glass types to consider that have similar optical properties, but different dn/dT
Type Code nc nd nF ng vd s.g. Coloring
S-BSL7 516641 1.51386 1.51633 1.52191 1.52621 64.14 2.52 330/285
S-LAH52 800422 1.79388 1.79952 1.81281 1.82355 42.22 4.41 400/330
S-LAH52Q 800422 1.79389 1.79952 1.81282 1.82356 42.24 4.47 390/335 More Info
S-LAH53 806409 1.80024 1.80610 1.81996 1.83117 40.92 4.49 405/340
S-LAH53V 806409 1.80026 1.80610 1.81995 1.83121 40.93 4.41 400/345
S-LAH60 834372 1.82738 1.83400 1.84982 1.86278 37.16 4.43 420/340
S-LAH60V 834372 1.82740 1.83400 1.84981 1.86283 37.21 4.43 430/350
S-LAH63 804396 1.79838 1.80440 1.81870 1.83034 39.59 4.34 410/340
S-LAH63Q 804396 1.79840 1.8044 1.81872 1.83043 39.58 4.45 415/345 More Info
S-LAL21 703524 1.69895 1.70300 1.71237 1.71976 52.38 3.85 395/320 More Info
S-LAL54 651562 1.64749 1.65100 1.65908 1.66543 56.16 3.82 365/325
S-LAL54Q 651562 1.64747 1.65100 1.65905 1.66532 56.24 3.36 385/- More Info
S-NPH1 808228 1.79801 1.80809 1.83351 1.85590 22.76 3.29 445/375
   
Open Near-infrared Properties of Dispersion
Wavelengths that are longer than the range visible to human eyes are designated as the infrared region. There are three types:
  • Far-infrared (FIR) – used primarily for thermography
  • Mid-infrared (MIR) – used primarily for laser processing
  • Near-infrared (NIR) – used at night or in dark environments for ‘night-vision’ camera
    Ohara supplies values for cameras used at NIR. Near-infrared Properties of Dispersion Automotive Cameras in Near-infrared (NIR) Optical lens systems used for automotive cameras need to have a certain degree of clear visibility at night as well as during the day.  If an optical system has been optimized to correct aberration in the visible region, the aberration in the near-infrared region (NIR) will still have issues with image blurring due to limited light. By correcting aberration up to NIR, clear images can be obtained during day or night. Automotive Cameras in Near-infrared (NIR) Glass types to consider that have unique Unique Glass
Type Code nc nd nF ng vd s.g. Coloring
S-FPL51 497816 1.49514 1.49700 1.50123 1.50451 81.54 3.62 340/290
S-FPL53 439950 1.43733 1.43875 1.44195 1.44442 94.93 3.62 330/275
S-FPL55 439948 1.43733 1.43875 1.44196 1.44444 94.66 3.59 335/290
S-BAL2 571508 1.56762 1.57099 1.57886 1.58514 50.80 2.89 370/335
S-BAL3 571530 1.56810 1.57135 1.57889 1.58489 52.95 2.98 360/330
S-LAH63Q 804396 1.79840 1.8044 1.81872 1.83043 39.58 4.45 415/345 More Info
S-LAL20 699511 1.69520 1.69930 1.70888 1.71647 51.11 4.38 370/310 More Info
S-LAL21 703524 1.69895 1.70300 1.71237 1.71976 52.38 3.85 395/320 More Info
S-LAM73 794371 1.78732 1.79360 1.80872 1.82119 37.09 4.45 415/350 More Info
S-NBH5 654397 1.64923 1.65412 1.66571 1.67517 39.68 3.02 370/325
S-NBH8 720347 1.71437 1.72047 1.73512 1.74723 34.71 3.19 390/330
S-NBH51 750353 1.74326 1.74950 1.76447 1.77681 35.33 3.29 400/330
S-NBH52V 673383 1.66779 1.67300 1.68538 1.69551 38.26 3.01 360/320
S-NBH53V 738323 1.73132 1.73800 1.75415 1.76762 32.33 3.19 385/330
S-NBH56 855248 1.84488 1.85478 1.87935 1.90045 24.80 3.49 (395)/360
S-NBH58 789284 1.78076 1.78880 1.80850 1.82518 28.43 3.33 410/345 More Info
S-NBM51 613443 1.60925 1.61340 1.62311 1.63091 44.27 2.93 350/320
S-NPH7 778239 1.76902 1.77830 1.80157 1.82191 23.91 3.30 420/370 More Info
S-PHM52 618634 1.61504 1.61800 1.62479 1.63010 63.33 3.67 370/325
S-PHM52Q 618633 1.61550 1.61800 1.62479 1.63008 63.32 3.51 365/325
S-PHM53 603655 1.60019 1.60300 1.60940 1.61438 65.44 3.51 360/300