JPH06112458A - Solid-state image sensing device - Google Patents

Abstract

PURPOSE:To enable a solid-state image sensing device to be free from smears and prevented from decreasing in sensitivity by a method wherein a refraction controller which converts light rays incident through a camera lens into parallel ray is provided between the cameral lens and a microlens. CONSTITUTION:A refraction controller 5 is provided between a cameral lens 4 and a microlens 1. Light passing through the camera lens 4 is refracted to be oblique rays so as to focus on a photodetective part 2. The oblique ray become parallel again passing through the refraction controller 5 and impinge on a mictrolens 1. Light ray refracted through the microlens 1 are made to impinge on a photodetective part 2. Therefore, light ray incident on the microlens 1 are parallel ray, the microlens 1 is able to guide parallel rays more efficiently to the photodetective part 2 than oblique ray. Consequently, incident light can be efficiently directed to the photodetective part 2. Therefore, a solid- state image sensing device of this design can be prevented from deteriorating in sensitivity and free from smears due to oblique ray incident on a photodetective part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state image pickup device.

[0002]

2. Description of the Related Art A conventional solid-state image pickup device will be described below with reference to FIG.
Will be described with reference to. FIG. 4 is a block diagram of a conventional solid-state imaging device. In FIG. 4, 1 is a micro lens, 2
Is a light receiving section of the solid-state imaging device, 3 is a light shielding section for preventing unnecessary light from entering, and 4 is a camera lens.

In this conventional solid-state image pickup device, incident light passing through the camera lens 4 is made incident on the light receiving portion 2 through the microlens 1. That is, the incident light is bent so as to be focused by the light receiving unit 2 by passing through the camera lens 4, and the incident light refracted by the camera lens 4 (hereinafter referred to as “oblique light”) is incident on the front surface of the light receiving unit 2. It is further refracted by the lens 1 and reaches the light receiving portion 2.

[0004]

However, in the above-mentioned conventional structure, the incident light is refracted by passing through the camera lens 4, so that the amount of oblique light also increases. The oblique light generated by the camera lens 4 is further bent by the microlens 1 and is incident on a portion other than the light receiving portion 2. If the light further obliquely refracted by the microlens 1 enters the portion other than the light receiving portion 2, it causes smear.
Further, the amount of light incident on the light receiving unit 2 is reduced accordingly, which causes a decrease in sensitivity.

The present invention solves the above-mentioned problems.
An object of the present invention is to provide a solid-state imaging device that can eliminate smear and sensitivity deterioration.

[0006]

The solid-state image pickup device of the present invention is characterized in that a refraction adjusting portion for converting incident light passing through the camera lens into parallel light is provided between the camera lens and the microlens.

[0007]

According to the structure of the present invention, the incident light which has passed through the camera lens is converted into parallel light by passing through the refraction adjusting portion and is incident on the microlens. Therefore, the microlens can efficiently guide the light to the light receiving portion, and smearing and reduction in sensitivity can be eliminated.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is a block diagram of a solid-state image pickup device according to a first embodiment of the present invention. In FIG. 1, reference numeral 5 denotes incident light that has passed through the camera lens 4 (hereinafter referred to as “oblique light”).
Is a refraction adjusting unit for converting light into parallel light, and is made of a material whose refractive index is adjusted so that oblique light can be converted into parallel light (two or more kinds of materials having different refractive indexes are overlapped). Note that the same reference numerals are given to those corresponding to FIG.

The solid-state image pickup device is characterized in that the refraction adjusting section 5 is provided between the camera lens 4 and the microlens 1. The incident light that has passed through the camera lens 4 is received by the light receiving unit 2
The light is refracted so that it is in focus and becomes an oblique light. This oblique light passes through the refraction adjusting unit 5 and becomes parallel light again and reaches the microlens 1. The light further refracted by the microlens 1 enters the light receiving unit 2.

According to this embodiment, the light incident on the microlens 1 is parallel light, and the microlens 1 is characterized in that it can efficiently guide light to the light receiving portion 2 when parallel light is incident rather than oblique light. Since it has, the incident light can be efficiently guided to the light receiving unit 2. As a result, it is possible to eliminate sensitivity deterioration and smear due to oblique light incidence. FIG. 2 is a block diagram of a solid-state imaging device according to the second embodiment of the present invention.

In this solid-state image pickup device, instead of the refraction adjusting section 5 in the first embodiment, a film having a refraction index adjusted above the microlens 1 (for example, an organic or inorganic resin having a refraction index of 1.5 or more). A refraction adjusting portion 6 made of a material is provided, and other configurations are similar to those of the first embodiment. The camera lens is not shown. The refraction adjusting unit 6 functions in the same manner as the refraction adjusting unit 5 in the first embodiment, converts oblique light generated by the camera lens 4 (see FIG. 1) into parallel light, and efficiently receives light. It is possible to eliminate the deterioration of sensitivity and smear due to the incidence of oblique light.

FIG. 3 is a block diagram of a solid-state image pickup device according to a third embodiment of the present invention. In this solid-state imaging device, a protective glass (refraction adjusting unit) 7 having an adjusted refractive index is arranged above a semiconductor chip 9 housed in a package 8. The protective glass 7 is transparent and has a role of converting oblique light generated by a camera lens (not shown) into parallel light, in addition to a normal role of preventing the semiconductor chip 9 from being damaged by an external factor. Since parallel light is emitted from the protective glass 7 to the microlens, the light can be efficiently guided to the light receiving portion, and sensitivity deterioration and smear can be eliminated.

[0013]

According to the solid-state image pickup device of the present invention, the refraction adjusting section for converting the incident light passing through the camera lens into parallel light is provided between the camera lens and the microlens.
The incident light that has passed through the camera lens is converted into parallel light by passing through the refraction adjusting unit and enters the microlens. Therefore, the microlens can efficiently guide the light to the light receiving portion, and smearing and reduction in sensitivity can be eliminated.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a solid-state imaging device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a solid-state imaging device according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a solid-state imaging device according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram of a conventional solid-state imaging device.

[Explanation of symbols]

 1 Microlens 2 Light receiving part 4 Camera lens 5 Refraction adjusting part 6 Refraction adjusting part 7 Protective glass (refraction adjusting part)

Claims (1)

[Claims] 1. A solid-state imaging device in which incident light that has passed through a camera lens is incident on a light receiving unit through a microlens, and a refraction adjusting unit that converts incident light that has passed through the camera lens into parallel light. Is provided between the camera lens and the microlens.