Electronic device, optical module and manufacturing process thereof
The present disclosure relates to an optical module, including: a carrier, a emitter, a detector and an encapsulant. The carrier has a first surface. The emitter is disposed above the first surface. The detector is disposed above the first surface. The encapsulant is disposed on the first surface and exposes at least a portion of the emitter.
1. An electronic device, comprising:
an optical module, comprising:
a carrier having a first surface;
an emitter disposed above the first surface;
a detector disposed above the first surface; and
an encapsulant covering at least a portion of the emitter at a side of the emitter facing the detector; and
a light-transmitting plate disposed above the optical module,
wherein at least a portion of an upper surface of the emitter is covered by the encapsulant and at least a portion of the upper surface of the emitter is exposed to air, and wherein a thickness of the encapsulant is configured so that the light emitted by the emitter to be incident on the light-transmitting plate has an incident angle less than a critical value θ th with respect to the light-transmitting plate,
wherein the encapsulant exposes a portion of the emitter, and the exposed portion of the emitter has a first edge and a second edge, the second edge is opposite to the first edge, and a distance between the second edge and the detector is less than a distance between the first edge and the detector, and wherein the side of the emitter facing the detector is the second edge;
wherein the encapsulant further exposes a portion of the detection, and the exposed portion of the detector further comprises a photosensitive region, the photosensitive region has a third edge and a fourth edge, the fourth edge is opposite to the third edge, and a distance between the fourth edge and the emitter is greater than a distance between the third edge and the emitter;
wherein the light-transmitting plate has a second surface and a third surface, and a distance between the third surface and the carrier is greater than a distance between the second surface and the carrier;
wherein the emitter is configured to emit the light emitted by the emitter to be incident on the light-transmitting plate at an incident angle θ 1 , the maximum value of the incident angle θ 1 is a critical value θ th , the critical value θ th meets a first equation n 1 sin θ th =n 2 sin θ 2 and a second equation: D=(h eg +h dg )tan θ th +2h g tan θ 2 , wherein n 1 is a refractive index of an intermediate medium disposed between the first surface and the light-transmitting plate, n 2 is an refractive index of the light-transmitting plate, θ 2 is a first refraction angle generated by the first light when entering into the light-transmitting plate at an incident angle of the critical value θ th , D is a distance between the first edge and the third edge, h eg is a distance between the upper surface of the emitter and the second surface of the light-transmitting plate, h dg is a distance between an upper surface of the photosensitive region and the second surface of the light-transmitting plate, and hg is a thickness between the second surface and the third surface of the light-transmitting plate.
2. The electronic device according to claim 1 , wherein the encapsulant at least laterally surrounds at least a portion of the detector, and exposes at least a portion of the detector.
3. The electronic device according to claim 1 , wherein the encapsulant is opaque.
4. The electronic device according to claim 1 , wherein the encapsulant transmits light.
5. The electronic device according to claim 1 , wherein the encapsulant is configured to block the light emitted from the emitter and having an incident angle of greater than or equal to the critical value θ th from entering the light-transmitting plate.
6. The electronic device according to claim 5 , wherein the emitter has a first thickness h 1 , the first edge and the second edge are spaced apart from each other at a first distance W, the encapsulant adjacent to the second edge has a second thickness at the second edge, the second thickness is greater than a minimum thickness value hmin, a difference between the minimum thickness value hmin and the first thickness h 1 of the emitter is h 2 , and h 2 meets the following equation: h 2 =Wcotθ th .
7. The electronic device according to claim 1 , wherein the critical value θ th is 25.7 degrees.
8. The electronic device according to claim 1 , wherein the emitter is a vertical-cavity surface-emitting laser.