CN2636507Y - Interleave muiltiplexing component element - Google Patents

Abstract

The utility model provides a wavelength division multiplex (WDM) module, which comprises a first transparent prism composed of a first cylindrical surface provided with a reflection reducing coating and a large incidence angle and a second cylindrical surface provided with a reflection reducing coating and a small incidence angle, a second transparent prism composed of a first cylindrical surface provided with a reflection reducing coating and a large incidence angle, a second and a third cylindrical surface respectively arranged with a reflection reducing coating and a small incidence angle. Wherein, an acute angle theta is formed by these two cylindrical surfaces of the first transparent prism. An acute angle Beta is formed by the first and the third cylindrical surface of the second transparent prism. In addition, the WDM module is additionally composed of a wave filter to closely connect with two corresponding first cylindrical surfaces of two transparent prisms, thus forming a narrow air gap and ensuring two second cylindrical surfaces of two transparent prisms in parallel. In addition, the wave filter closely clings to the second cylindrical surface of the second transparent prism to form the other narrow air gap, thus achieving the optimal separation between an incoming light and an outgoing light at a short distance. The utility model is suitable for dense wavelength multiplex module with a plurality of wavelengths to effectively reduce module size.

Description

Interleave muiltiplexing component element

Technical field

The utility model relates to optical communication field, more particularly, relates in particular to Interleave muiltiplexing component element.

Background technology

In existing close wavelength-division multiplex technology, usually adopt by the wavelength division multiplexer cascade of structure as shown in Figure 1 to form.In this kind structure, bigger than manufacturing difficulty with the filter of low-angle incident with the filter of wide-angle incident, this mainly is because s light and p light difference in reflectivity when wide-angle are bigger.When low-angle was incident to filter, its incident light and reverberation separately needed long distance, cause the Interleave muiltiplexing component element volume big.

In addition, in the structure of existing single fiber bi-directional two-port transceiver module, the most frequently used is two wavelength of transmitted in both directions 1310nm/1550nm, or three wavelength of transmission 1310nm/1490nm/1550nm in the structure of single fiber bi-directional three port transceiver modules.In these two kinds of structures, all about 45 degree of the incident angle of its filter plate, incident light is almost vertical with reverberation.But, have only the demand of the single fiber bi-directional two-port transceiver module of light of 20nm wavelength around or single fiber bi-directional three port transceiver modules more and more urgent for the transmission spacing along with the development of cable TV network technology.It is 45 degree wavelength division multiplexing diaphragms that the light time of transmitting the 1510/1530nm wavelength is if desired still adopted incident angle, and then manufacture difficulty will be very big, so also can improve the cost of manufacture of device greatly.

Summary of the invention

For overcoming above shortcoming, it is a kind of with low-angle incident that the utility model provides, the Interleave muiltiplexing component element that incident light and reverberation distance of separation are short.

A kind of Interleave muiltiplexing component element comprises: a refractive index is n ₁The first transparent prism, comprise being coated with wide-angle incident anti-reflection film first cylinder and be coated with low-angle incident anti-reflection film second cylinder that the angle between this two cylinder is an acute angle theta; One refractive index is n ₁The second transparent prism, comprise being coated with wide-angle incident anti-reflection film first cylinder, being coated with low-angle incident anti-reflection film cylinder second and the 3rd cylinder that the angle of its first cylinder and the 3rd cylinder is an acute angles beta; One filter plate; It is n that two corresponding first cylinders of described two transparent prisms are close to formation one refractive index mutually ₂Narrow air-gap, and second cylinder of two transparent prisms is parallel to each other, filter plate is close to second cylinder of the second transparent prism and is formed another narrow air-gap, described acute angle theta satisfies following formula:

$\arcsin \left(\frac{n_2}{n_1}\right)-\frac{n_2}{{\mathrm{<figure-callout\; id="1"\; label="n"\; filenames="Y0327394100071.png,Y0327394100072.png"\; state="\{\{state\}\}">n</figure-callout>}}_1}\sin \mathrm{\&alpha;}\&le;\mathrm{\&theta;}\&le;\arcsin \left(\frac{n_2}{n_1}\right)+\frac{n_2}{{\mathrm{<figure-callout\; id="1"\; label="n"\; filenames="Y0327394100071.png,Y0327394100072.png"\; state="\{\{state\}\}">n</figure-callout>}}_1}\sin \mathrm{\&alpha;}$

Because in the above-mentioned Interleave muiltiplexing component element structure, the incident light of filter plate and catoptrical light path have all been passed through a pair of prism assemblies, and prism can not produce loss to it, and the second transparent prism can be with 90 °-140 ° of the light deflections that reflect back from filter, thereby the incident light and the optimal separation of reverberation in short distance of filter plate have been realized, this device is suitable for the dense wave division multipurpose module of a plurality of wavelength, can effectively reduce the volume of module.

Description of drawings

Fig. 1 is existing wavelength division multiplexer structural representation.

Fig. 2 is a kind of structural representation of the utility model Interleave muiltiplexing component element.

Embodiment

Interleave muiltiplexing component element as shown in Figure 2 comprises: the first transparent triangular prism 1 comprises three cylinder 1A, 1B and 1C, wherein, the angle that cylinder 1A and cylinder 1B form is θ, and it approximately is 12 °-42 ° angle β that cylinder 1A and cylinder 1C form, and gets β=41 ° at this.The second transparent triangular prism 2, comprise three cylinder 2A, 2B and 2C, its shape is identical with the first transparent triangular prism 1, the angle that is corresponding cylinder formation is identical, and their material is BK7 glass, refractive index is 1.5, triangular prism 1 and 2 is close to the back mutually with cylinder 1A and 2A respectively and is formed a parallelogram prism, promptly corresponding two cylinders of all the other of two triangle prisms are parallel, it is 1 narrow air-gap 4 that a refractive index is left in the centre, be close to a filter plate 3 on the cylinder 2B of triangular prism 2, and the middle refractive index that leaves is 1 narrow air-gap 5.As (λ 1 λ 2 of the light beam 61 with a plurality of wavelength ... λ n) with incidence angle α during from the 1B face incident of the first transparent triangular prism 1, the span of incidence angle α is at 4 °-12 °, choose α=7.5 ° at this, because cylinder 1A is coated with the anti-reflection film of big incidence angle, so light beam can all be transmitted through air-gap 4, the value of θ must satisfy following formula:

$\arcsin \left(\frac{n_2}{n_1}\right)-\frac{n_2}{{\mathrm{<figure-callout\; id="1"\; label="n"\; filenames="Y0327394100071.png,Y0327394100072.png"\; state="\{\{state\}\}">n</figure-callout>}}_1}\sin \mathrm{\&alpha;}\&le;\mathrm{\&theta;}\&le;\arcsin \left(\frac{n_2}{n_1}\right)+\frac{n_2}{{\mathrm{<figure-callout\; id="1"\; label="n"\; filenames="Y0327394100071.png,Y0327394100072.png"\; state="\{\{state\}\}">n</figure-callout>}}_1}\sin \mathrm{\&alpha;}$

n ₁The refractive index of representing transparent prism, n ₂The refractive index of expression air.By calculating, the θ span is 36.8 °-46.8 °, get θ=37 ° at this, light beam passes the cylinder 2A that is incident to second transparent triangular prism 2 behind the air-gap 4 again, because cylinder 2B is coated with the anti-reflection film of low-angle incident, then light beam can be all by forming irradiating light beam 62 (λ 1 λ 2 after the cylinder 2B transmission ... λ n), because this light beam process is the transparent parallelogram prism that is made of two transparent triangular prisms 1 and 2, then incident beam 61 (λ 1 λ 2 ... λ n) and outgoing beam 62 (λ 1 λ 2 ... λ n) be parallel.Again because the plane of incidence 3A of the cylinder 2B of the cylinder 1B of the first transparent triangular prism 1 of light beam process, the second transparent triangular prism 2 and filter 3 is parallel to each other, incident angle when then light beam 62 is incident to filter 3 by narrow air-gap 5 also is 7.5 °, and transmit the light 63 of a predetermined wavelength lambda 1, (λ 2 to reflect its commplementary wave length ... λ n) light 64.Light beam 64 after the process reflection is after the cylinder 2B incident of the second transparent triangular prism 2, reenter and be incident upon cylinder 2A, about 42 degree of its incidence angle, this angle is greater than the angle of total reflection 41.8 of glass material, (λ 2 so can produce whole reflection wavelengths ... λ n) light beam 65.So far light beam 65 relative light beam 64 twice deflection, for the first time 2.5 ° of the cylinder 2B of the second transparent triangular prism 2 deflections, at the cylinder 2A of the second transparent triangular prism 2, deflection 84 is spent for the second time, and deflection is 86.5 ° altogether.Total reflection light beam 65 all transmits through cylinder 2C.Above-mentioned β value can be in a very big scope value, different values will change the direction of total reflection light beam 65.Total reflection light beam 65 is then chosen suitably littler β value near incident light 61 if desired; Total reflection light beam 65 more close transmitted light beams 64 if desired, the β value is done greatly.

Claims (2)

1, a kind of Interleave muiltiplexing component element is characterized in that, comprising:

The first transparent prism (1), its refractive index is n ₁, comprising anti-reflection film first cylinder (1A) that is coated with wide-angle incident, anti-reflection film second cylinder (1B) that is coated with low-angle incident, cylinder (1A) is an acute angle theta with the angle of cylinder (1B);

The second transparent prism (2), its refractive index is n ₁, comprising anti-reflection film first cylinder (2A) that is coated with wide-angle incident, the anti-reflection film cylinder second (2B) that is coated with low-angle incident and the 3rd cylinder (2C), cylinder (2A) is an acute angles beta with the angle of cylinder (2C):

One filter plate (3);

Two corresponding cylinder 1A of described two transparent prisms (1) and (2) and 2A are close to mutually that to form a refractive index be n ₂Narrow air-gap (4), and second cylinder (1B) of the first transparent prism (1) and second cylinder (2B) of the second transparent prism (2) are parallel to each other, filter plate (3) is close to second transparent prism (2) second cylinders (2B) and is formed another narrow air-gap (5), and the value of θ must satisfy following formula:

$\arcsin \left(\frac{n_2}{n_1}\right)-\frac{n_2}{n_1}\sin \mathrm{\&alpha;}\&le;\mathrm{\&theta;}\&le;\arcsin \left(\frac{n_2}{n_1}\right)+\frac{n_2}{n_1}\sin \mathrm{\&alpha;}.$

2, Interleave muiltiplexing component element according to claim 1 is characterized in that, described θ span is 36.8 °-46.8 °.

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