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combination of thin lenses in contact

It is a transparent medium bounded by two surfaces, and one of them must be curved. The lens is thin if the gap between the two surfaces is small.

Nature has endued the human eye (retina) with the sensitivity to sight magnetism waves during various electromagnetic spectrums. The radiation happiness to the current region of this spectrum (wavelength of concerning four hundred nm at 750 nm) is named light. It’s primarily through light and, therefore, the sense of sight that we all know and interpret the planet around us.

Power of a lens 

The power of a lens may be a life of the degree of convergence or divergence of sunshine falling on it. the ability of a lens (P) is outlined because the reciprocal of its distance P=1/f

The unit of measure is the unit of measurement (D): one D = 1 m⁻¹. The lens capacitance is assumed to be 1 diopter if the lens focal length is 1 meter. P is positive for the lens system and negative for the diverging lens. Thus once a lens maker prescribes a corrective lens of power + 0.5 D, the desired lens may be a convex lens of focal length + two m. an influence of -2.0 D indicates a diverging lens with a focal length of -0.5 m

Combination of thin lenses

Compound lenses are the type of lenses that have two thin lenses mounted on a common axis that are generally closer to each other or often glued together.

The following formula gives the common focal length for a system, where two subtle lenses sharing an axis are maintained in contact with each other is provided by the following formula

1/f = 1/f1 + 1/f2 

f, combined focal length

f1, the focal length of the first lens

f2, the focal length of the second lens

Since power is the reciprocal of focal length, what is very obvious in this case? For thin contact lenses, it is quite evident that the system’s combined power is given by the sum of the powers of the individual lenses.

But what if the lenses aren’t in contact with each other? If the lenses are separated by a distance “d”, then, in this case, the combination of focal length can be calculated using the following formula.

1/f = 1/f1 + 1/f2 – d/f1.f2

While dealing with the combination of lenses or compound lenses, you may come across the following terms.

Combination of thin contact lenses

Once two lenses are combined, the primary forms a picture that then is AN object for the second lens. The magnification of the mix is the magnitude relation of the peak of the ultimate image to the height of the article. This can be the final image made by the combination of lenses. Think about two lenses, A and B, with focal lengths f1 and f2 placed in reality with each other. Since the lenses are thin, we tend to assume that the optical centers of the lenses coincide. The primary lens produces an I1 image. Since image I1 is real, it is a virtual object for the second lens B, manufacturing the ultimate image at I. However, it is essential to remember that the primary lens is likely to generate an image only to aid in determining the position of the final image. The direction of rays rising from the first lens gets changed in accordance with the angle at which they strike the second lens. Since the lenses are thin, we tend to assume that the optical centers of the lenses coincide. Let this central purpose be denoted by P.

Lens Formula 

The Lens Formula is an equation that shows the relationship between focal length, object distance, and image distance.

  • The lens formula is for lenses with very thin thickness.
  • Both convex and concave lenses are affected by the Lens Formula.
  • The Lens-Maker’s Formula is used to create the Lens Formula.
  • The focal length of the lens is determined using the lens formula.

Mathematically, 

The reciprocal of a lens’s focal length equals the sum of its object and image distance reciprocals.

It is given by,

1p+1q=1f

where,

p = object distance

q = image distance

f = focal length of the lens

Conclusion

Glasses, contact lenses, telescopes, binoculars, magnifying glasses, and pretty much any optical equipment employ lenses. It emphasises the significance of lenses and the importance of determining the combination of thin lenses in contact for varied purposes. Optical experts devised a lens formula, which was primarily used to determine the equivalent power of lenses. We can deduce from the preceding explanation that:

  • The lens’s relationship between the focal length, object distance, and image distance is shown in the Lens Formula.
  • If we know the other two lens dimensions, it will be easier to figure out the unknown variable.
  • It is only suitable for ultra-thin lenses. The good news is that we see in our daily lives through thin glasses.
  • The equivalent power of a combination of thin lenses in contact also aids in determining the lens’ magnification and power.
  • The thin lens formula is written as 1/f = 1/v + 1/u in math.
  • P = 1 f is the mathematical expression of a lens’s power.

M = v/u is the mathematical form of magnification.